Actionlint workflow checking

[jplomas]

Based on open-quantum-safe/liboqs#1916, this integrates Actionlint checking of GitHub workflows for errors as part of CI. This also fixes issues highlighted in other workflows, primarily the checkout version and missing property.

For completeness, the actionlint output for the workflows before the fixes applied in this PR:

| .github/workflows/coding_style.yml:17:15: the runner of "actions/checkout@v2" action is too old to run on GitHub Actions. update the action's version to fix this issue [action]
|    |
| 17 |         uses: actions/checkout@v2
|    |               ^~~~~~~~~~~~~~~~~~~
| .github/workflows/linux.yml:26:15: the runner of "actions/checkout@v2" action is too old to run on GitHub Actions. update the action's version to fix this issue [action]
|    |
| 26 |         uses: actions/checkout@v2
|    |               ^~~~~~~~~~~~~~~~~~~
| .github/workflows/linux.yml:56:15: the runner of "actions/checkout@v2" action is too old to run on GitHub Actions. update the action's version to fix this issue [action]
|    |
| 56 |         uses: actions/checkout@v2
|    |               ^~~~~~~~~~~~~~~~~~~
| .github/workflows/linux.yml:106:15: the runner of "actions/checkout@v2" action is too old to run on GitHub Actions. update the action's version to fix this issue [action]
|     |
| 106 |         uses: actions/checkout@v2
|     |               ^~~~~~~~~~~~~~~~~~~
| .github/workflows/linux.yml:180:15: the runner of "actions/checkout@v2" action is too old to run on GitHub Actions. update the action's version to fix this issue [action]
|     |
| 180 |         uses: actions/checkout@v2
|     |               ^~~~~~~~~~~~~~~~~~~
| .github/workflows/standalone.yml:21:15: the runner of "actions/checkout@v2" action is too old to run on GitHub Actions. update the action's version to fix this issue [action]
|    |
| 21 |         uses: actions/checkout@v2
|    |               ^~~~~~~~~~~~~~~~~~~
| .github/workflows/standalone.yml:49:15: the runner of "actions/checkout@v2" action is too old to run on GitHub Actions. update the action's version to fix this issue [action]
|    |
| 49 |         uses: actions/checkout@v2
|    |               ^~~~~~~~~~~~~~~~~~~
| .github/workflows/windows.yml:60:60: property "config" is not defined in object type {arch: string; oqsconfig: string} [expression]
|    |
| 60 |         run: bash -c "./config --prefix=/opt/openssl32 ${{ matrix.platform.config }} && perl configdata.pm --dump && make $MAKE_PARAMS && make install_sw"
|    |                                                            ^~~~~~~~~~~~~~~~~~~~~~
[Check GitHub workflows/Check validity of GitHub workflows]   ❌  Failure - Main Ensure GitHub actions are valid

[baentsch]

LGTM. Much appreciated, @jplomas !

[baentsch]

Before landing this, just a question whether you'd be interested to help this project more long term and would want to add yourself as part of this PR to

oqs-provider/.github/CODEOWNERS

Line 8 in 8abfecd

/.github/workflows @baentsch @thb-sb

@jplomas ?

[jplomas]

Before landing this, just a question whether you'd be interested to help this project more long term and would want to add yourself as part of this PR to

oqs-provider/.github/CODEOWNERS

Line 8 in 8abfecd

/.github/workflows @baentsch @thb-sb

@jplomas ?

Happy to help where I can.