CI: Highlighting flake8 and grep errors in GitHub Actions

[datapythonista]

Our code checks genereated the output in a way that Azure pipelines was highlighting the errors. In GitHub actions it's possible to do more or less the same, but with a different syntax. Changing the syntax here, and simplifying some tricky parts in the script.

Introducing some errors, so we can see how it looks.

[pep8speaks]

Hello @datapythonista! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file pandas/__init__.py:

Line 20:56: W291 trailing whitespace
Line 24:27: W291 trailing whitespace

Comment last updated at 2019-11-28 14:31:10 UTC

[jbrockmendel]

neat

[alimcmaster1]

This might a different issue but I think all steps should run and not just exit when a step fails.

Its annoying to fix one issue only to be confronted by another on the next run. What do you think?

[datapythonista]

This might a different issue but I think all steps should run and not just exit when a step fails.

I think this is a problem with GitHub. This was working as expected, and the configuration didn't change. If they don't fix it in couple of days I'll report it, and see what they say.

[jreback]

thanks