DM-47403: Fix problems in GitHub build workflow

[JeremyMcCormick]

Fix issues in the build workflow:

1. Use the standard workflow trigger instead of on: push
2. Add fetch-depth: 0 to checkout
3. Build and push Docker images on all triggers, including for user branches and merges to main
4. Update the tap-schema/build script so it creates Docker images with the proper names for all cases (tags, branches & PRs)

Miscellaneous changes:

1. Remove a commented-out column from imsim
2. Add lsst versions file and config.log to .gitignore

[timj]

I confirm that the version code now works

lsst-sdm-schemas==28.2024.4403 (from file:///home/runner/work/sdm_schemas/sdm_schemas)