GHA: Test on Ubuntu 20.04 LTS (Focal Fossa)

[hugovk]

Now available in preview.

The list of the tools that are not available on Ubuntu 20.04 yet (It should be available in a few weeks):

1. Docker
2. Pre-cached versions of Python, PyPy, Ruby, Node (setup-python / UsePython, setup-ruby / UseRuby tasks may not work properly due to that).

actions/runner-images#228 (comment)

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However the deadsnakes versions pass ✅

• tinytext/.github/workflows/test.yml

  Lines 18 to 29 in e98981b

  	# Dev versions
  	- { python-version: 3.9-dev, os: ubuntu-18.04 }
  	- { python-version: 3.10-dev, os: ubuntu-18.04 }
  	steps:
  	- uses: actions/checkout@v2
  	- name: Set up Python ${{ matrix.python }} (deadsnakes)
  	uses: deadsnakes/action@v1.0.0
  	if: endsWith(matrix.python-version, '-dev')
  	with:
  	python-version: ${{ matrix.python-version }}

[codecov]

Codecov Report

Merging #43 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master       #43   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            2         2           
  Lines           13        13           
=========================================
  Hits            13        13           

Flag	Coverage Δ
#GHA_Ubuntu1604	100.00% <ø> (ø)
#GHA_Ubuntu1804	100.00% <ø> (ø)
#GHA_Ubuntu2004	100.00% <ø> (?)
#GHA_macOS	100.00% <ø> (ø)
#TravisCI	100.00% <ø> (ø)

---

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[hugovk]

🚀 Ready!

• Add Ubuntu 20.04 focal actions/runner-images#228 (comment)