GHA release workflow, refactor PR and Daily workflows

[bandish-shah]

What does this PR do?

• Adds a release.yaml pipeline which can be triggered by the creation of a properly formatted tag (beginning with a 'v') or manually by repo admins. The pipeline does the following:

  1. Runs code quality checks
  2. Builds source and wheel distributions
  3. Publishes PyPi production packages if triggered by by the push of a tag. Otherwise builds and pushes packages to Test PyPi.
  4. Builds and pushes production Docker images if triggered by the push of a tag, skipped otherwise. Production Docker build and push can be performed independently by triggering the release-docker pipeline manually.

• Adds a release-docker.yaml pipeline which builds and pushes production Docker images. This flow can be triggered manually by repo admins

• Adds coverage, pytest-cpu, pytest-gpu and docker-configure-build-push reusable workflows

• Adds/refactors PR pr-docker, pr-cpu, pr-gpu pipelines to use reusable workflows

• Refacxtors pytest-daily to daily pipeline and uses reusable workflows

Future Work (addressed by future PRs)

• Update daily to build Docker images and run tests on staged images
• Update Composer Docker builds to be gated by PyTorch images

What issue(s) does this change relate to?

Closes CO-1186

Testing

All workflows were tested manually by adding the pull_request trigger to all workflows and running in GHA. This trigger has been removed from the daily, release-docker and release workflows. The pr-gpu workflow has been changed to use the pull_request_target workflow since it needs to provide secrets to PR's from forked repos. Links to passing GHA runs for these workflows can be found below.

pr-gpu: https://github.com/mosaicml/composer/actions/runs/4199439168

daily: https://github.com/mosaicml/composer/actions/runs/4208510415

release-docker: https://github.com/mosaicml/composer/actions/runs/4208510424

release: https://github.com/mosaicml/composer/actions/runs/4210173449

Before submitting

• Have you read the contributor guidelines?
• Did you update any related tests and add any new tests related to your change? (see testing)
• Did you run pre-commit on your change? (see the pre-commit section of prerequisites)

[dakinggg]

Blocking because of my question about secrets, otherwise LGTM and we can ship and fix

[mvpatel2000]

Mostly LGTM. Left 1 minor comment, and also confused by Daniel's points on python 3.9 and the push: false. Once this is approved, we can:

1. update settings to remove old required tests
2. merge this in
3. update required tests

OR

1. force merge this in
2. update required tests

Former is has a small window of tests are not required so it's not ideal, but latter uses force merging which is kinda nasty. Will let you pick whatever you want

[mvpatel2000]

LGTM. There's enough moving pieces though that I would not merge until @dakinggg also approves

[dakinggg]

LGTM, lets see if it works!