Jupyter Web Apps: Build + Push to ACR on PR

[Collinbrown95]

Description

Instead of pushing commits to main to test the image, can we run the build.yml and publish.yml workflows on pull request events? I think this should be possible with something like https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#pull_request

CC @Souheil-Yazji

[Jose-Matsuda]

If this is just for jupyter-apis I think we have something in place for that (now, not at time of original writing) as seen here (issue)

Having said that, the change here (that triggers on prs with the auto-deploy tag pushes to the regular acr and not the dev acr. This is more for the cleaning task of the acrs where say for the dev one we do a full clean and for the regular acr we keep a history of the last 5 images.

[mathis-marcotte]

After discussing it, we will just update the auto-deploy tag to have it push to the dev ACR instead of the regular ACR