gen-payload: raise an error if assembly is not explicitly defined

[vfreex]

This will prevent release artists from unexpectedly running gen-payload
before updating releases.yml.

[openshift-bot]

Build #1

GLOB sdist-make: /mnt/workspace/jenkins/working/art-tools_doozer_PR-502/setup.py
py3 create: /mnt/workspace/jenkins/working/art-tools_doozer_PR-502/.tox/py3
py3 installdeps: -rrequirements-dev.txt
py3 inst: /mnt/workspace/jenkins/working/art-tools_doozer_PR-502/.tox/.tmp/package/1/rh-doozer-1.3.18.zip
py3 installed: WARNING: The directory '/.cache/pip' or its parent directory is not owned or is not writable by the current user. The cache has been disabled. Check the permissions and owner of that directory. If executing pip with sudo, you should use sudo's -H flag.,aiofiles==0.7.0,astroid==2.7.2,attrs==21.2.0,autopep8==1.5.7,backports.entry-points-selectable==1.1.0,bashlex==0.15,cached-property==1.5.2,certifi==2021.5.30,cffi==1.14.6,charset-normalizer==2.0.4,click==8.0.1,contextvars==2.4,coverage==5.5,cryptography==3.4.8,decorator==5.0.9,Deprecated==1.2.12,distlib==0.3.2,dockerfile-parse==1.2.0,filelock==3.0.12,flake8==3.9.2,flexmock==0.10.7,future==0.18.2,gssapi==1.6.14,idna==3.2,immutables==0.16,importlib-metadata==4.7.0,importlib-resources==5.2.2,iniconfig==1.1.1,isort==5.9.3,kobo==0.19.0,koji==1.26.0,lazy-object-proxy==1.6.0,mccabe==0.6.1,mock==4.0.3,mysql-connector-python==8.0.26,packaging==21.0,platformdirs==2.2.0,pluggy==0.13.1,protobuf==3.17.3,py==1.10.0,pycodestyle==2.7.0,pycparser==2.20,pyflakes==2.3.1,pygit2==1.6.1,PyGithub==1.55,PyJWT==2.1.0,pykerberos==1.2.1,pylint==2.10.2,PyNaCl==1.4.0,pyparsing==2.4.7,pytest==6.2.4,python-dateutil==2.8.2,PyYAML==5.4.1,requests==2.26.0,requests-gssapi==1.2.3,requests-kerberos==0.12.0,rh-doozer @ file:///mnt/workspace/jenkins/working/art-tools_doozer_PR-502/.tox/.tmp/package/1/rh-doozer-1.3.18.zip,rpm==4.14.3,rpm-py-installer==1.1.0,semver==2.13.0,six==1.16.0,tenacity==8.0.1,toml==0.10.2,tox==3.24.3,typed-ast==1.4.3,typing==3.7.4.3,typing-extensions==3.10.0.0,urllib3==1.26.6,virtualenv==20.7.2,wrapt==1.12.1,zipp==3.5.0
py3 run-test-pre: PYTHONHASHSEED='2971081679'
py3 run-test: commands[0] | flake8
py3 run-test: commands[1] | coverage run --branch --source doozerlib -m unittest discover -t . -s tests/
........................................................................s.s....................................s.s...s.s.s..s.s.s....................................................................................................................
----------------------------------------------------------------------
Ran 235 tests in 9.747s

OK (skipped=10)
py3 run-test: commands[2] | coverage report
Name                                    Stmts   Miss Branch BrPart  Cover
-------------------------------------------------------------------------
doozerlib/__init__.py                      11      4      2      1    62%
doozerlib/assembly.py                     153     50     87      8    63%
doozerlib/assembly_inspector.py           162    144     92      0     7%
doozerlib/assertion.py                     22      0      6      0   100%
doozerlib/brew.py                         340    195    148      3    39%
doozerlib/build_status_detector.py         85     10     54      3    86%
doozerlib/cli/__init__.py                 101     45     20      0    46%
doozerlib/cli/__main__.py                1221   1221    510      0     0%
doozerlib/cli/cli_opts.py                  16      3      6      0    86%
doozerlib/cli/config_plashet.py           533    533    248      0     0%
doozerlib/cli/detect_embargo.py           163     35     70      8    75%
doozerlib/cli/images_health.py             79     28     24      2    61%
doozerlib/cli/images_streams.py           556    556    232      0     0%
doozerlib/cli/release_gen_assembly.py     166    166     82      0     0%
doozerlib/cli/release_gen_payload.py      330    272    170      0    12%
doozerlib/cli/rpms_build.py               165     59     58      8    57%
doozerlib/cli/scan_sources.py             178    146     94      2    14%
doozerlib/config.py                        98     98     44      0     0%
doozerlib/constants.py                      9      0      0      0   100%
doozerlib/coverity.py                     238    209     74      0     9%
doozerlib/dblib.py                        248    152     68      4    35%
doozerlib/distgit.py                     1380    915    642     15    31%
doozerlib/dotconfig.py                     56     44     32      0    14%
doozerlib/exceptions.py                     3      0      0      0   100%
doozerlib/exectools.py                    194     75     76     17    56%
doozerlib/gitdata.py                      168    133     76      0    14%
doozerlib/image.py                        488    321    212      6    28%
doozerlib/logutil.py                       10      0      2      1    92%
doozerlib/metadata.py                     444    172    202     30    56%
doozerlib/model.py                        111     21     36      2    82%
doozerlib/olm/__init__.py                   0      0      0      0   100%
doozerlib/olm/bundle.py                   282    216     64      0    19%
doozerlib/operator_metadata.py            364     65     66      6    79%
doozerlib/plashet.py                      134      9     90     15    89%
doozerlib/pushd.py                         21      2      2      0    91%
doozerlib/repos.py                        207    105    113     17    44%
doozerlib/rhcos.py                        111     30     32      4    66%
doozerlib/rpm_builder.py                  226     31    121     32    81%
doozerlib/rpmcfg.py                       141     56     58      8    56%
doozerlib/runtime.py                      892    648    364      8    21%
doozerlib/source_modifications.py          89     28     18      3    65%
doozerlib/state.py                         24     12      8      0    38%
doozerlib/util.py                         336    136    118      5    56%
-------------------------------------------------------------------------
TOTAL                                   10555   6945   4421    208    31%
___________________________________ summary ____________________________________
  py3: commands succeeded
  congratulations :)

[codecov-commenter]

Codecov Report

Merging #502 (fff2d9f) into master (e549833) will increase coverage by 32.23%.
The diff coverage is 33.33%.

@@             Coverage Diff             @@
##           master     #502       +/-   ##
===========================================
+ Coverage        0   32.23%   +32.23%     
===========================================
  Files           0       42       +42     
  Lines           0    10555    +10555     
  Branches        0     2208     +2208     
===========================================
+ Hits            0     3402     +3402     
- Misses          0     6945     +6945     
- Partials        0      208      +208     

Impacted Files	Coverage Δ
doozerlib/cli/release_gen_payload.py	17.57% <33.33%> (ø)
doozerlib/distgit.py	32.60% <0.00%> (ø)
doozerlib/assembly.py	62.09% <0.00%> (ø)
doozerlib/cli/rpms_build.py	59.39% <0.00%> (ø)
doozerlib/gitdata.py	20.83% <0.00%> (ø)
doozerlib/rpmcfg.py	54.60% <0.00%> (ø)
doozerlib/assertion.py	100.00% <0.00%> (ø)
doozerlib/rpm_builder.py	72.12% <0.00%> (ø)
doozerlib/source_modifications.py	65.16% <0.00%> (ø)
doozerlib/metadata.py	54.50% <0.00%> (ø)
... and 33 more

---

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