Add env variables to python lint test workflow

[SonOfLope]

Two pull request with new env variables not included in the workflow are currently failing.

• https://github.com/ai-cfia/nachet-metadata-format/actions/runs/8457722680/job/23170338549?pr=5
• https://github.com/ai-cfia/api-test/actions/runs/8458483501/job/23216581844?pr=9

For now, we will fix this by manually adding them. The following issue is open to provide a dynamic solution : https://github.com/ai-cfia/howard/issues/24