🧑‍💻Improve make tests-all-local

[sjasonsmith]

Description

This resolves several issues encountered when running make tests-all-local. These were found when operating inside Windows Subsystem for Linux, but likely impacted other development environments as well:

1. Tests continued after failing a TEST_TARGET. This made it difficult to notice when a failure occurred. By adding a test for status and an exit(1) call on failure, the test sequence now stops as soon as a failure occurs.

2. PlatformIO frequently failed to transition from one test target to the next, with errors indicating missing frameworks. This seems to be resolved by adding a 5 second delay when transitioning from one TEST_TARGET to the next.

3. Test the local Python to ensure pyyaml is available. If not, instruct user how to install it.
   I chose not to install it automatically, since this is the user's default Python and not a virtual environment.

4. Fix broken file reference, and do not require Python files to be made executable to work.

Requirements

• Linux-like development environment with make and other Marlin dependencies installed
• Execute make tests-all-local from the command line

Benefits

Simplified running compilation tests locally to test changes outside of a PR.

[sjasonsmith]

@thisiskeithb would you be able to test this on macOS to make sure I haven't broken your workflow while fixing my own?

[sjasonsmith]

There are apparently some more changes I need to make. I think I edited some other files that I forgot to check in.

[thisiskeithb]

I've not had good luck with running most of Marlin's scripts, so I usually send them off to GitHub and let CI handled them.

I still have the same Permission denied error when trying to run make tests-single-local / make tests-all-local unless I run chmod +x get_test_targets.py before they'll attempt to run. Could all of these scripts be set to executable by default like we do for files in Marlin/buildroot/tests/? Or somehow automate it? Switching branches / testing out all kind of forks makes this a pain.

Once I make get_test_targets.py executable and run make tests-single-local TEST_TARGET=FYSETC_F6, it has several macros.h warnings, but works:

Passed
All tests completed successfully

Running make tests-all-local, it fails with a new error (same error I get before this PR):

Traceback (most recent call last):
  File "/Marlin/buildroot/share/scripts/get_test_targets.py", line 11, in <module>
    with open(yaml_file) as f:
         ^^^^^^^^^^^^^^^
FileNotFoundError: [Errno 2] No such file or directory: '.github/workflows/test-builds.yml'

I documented some of these issues & potential fixes in #26904 (comment), but it would be really handy if there was a set of instructions somewhere that had the list of prerequisites on what all needs to be installed / set to executable or automate it so this process is easier.

Tested on macOS Monterey

[thisiskeithb]

After your latest commits... Success!

Passed
All tests completed successfully

Tested on macOS Monterey

[sjasonsmith]

After your latest commits... Success!

Passed
All tests completed successfully

Tested on macOS Monterey

Thanks for testing it out, and I'm glad we could fix the macOS failure!