Add pylint to github actions.

[AllynH]

Copy the Run CSV validation tests job and add pylint:
The command pylint tests/. passes locally.

The job can be added to the bottom of: https://github.com/PythonIreland/python_ireland_event_resources/blob/main/.github/workflows/validate-csv.yml

You can copy the pytest example.

[ZichengLiang]

Hi Allyn!

I'd like to try this!

[AllynH]

Resolved in merge:
#22

[AllynH]

Nice job @ZichengLiang 👏