Include diff file in test-scraper.yml Action artifact

[dphoria]

Feature Description

A comment in the form /test-scraper --from_dt=<iso-formatted-datetime> --to_dt=<iso-formatted-datetime> get_{municipality_slug}_events in a pull request or an issue triggers the GitHub Action .github/workflows/test-scraper.yml. The Action uploads a ZIP file as an artifact. The ZIP contains a JSON file for the scraped events returned by cdp_scrapers.instances.get_{municipality_slug}_events().

If the Action was triggered by a pull request comment, it would be helpful to also include a diff file, comparing the results from the same call between the pull target branch (CouncilDataProject/cdp-scrapers main) and the pull merge branch.

Change summary:

1. Do something similar to what test-scraper.yml does currently: save scraped events in JSON file.
2. Repeat, using CouncilDataProject/cdp-scrapers main.
3. Save output from diff between the two JSON files.
4. Add the diff file in the ZIP file artifact for the Action.

Use Case

Often we find ourselves manually creating this kind of diff files to study changes (if any) some new code would yield in the scraped IngestionModels. Doing so automatically for a pull request /test-scraper run would reduce manual effort.

Solution

File(s) in .github/workflows/ (and subdirectories) updated as necessary to include diff files, described above, in the artifact ZIP.

[evamaxfield]

YES SUNG. This would be amazing. ♥️♥️♥️