Merge branch 'js/ci-ghwf-dedup-tests'

The logic to skip testing on the tagged commit and the tag itself
was not quite consistent which led to failure of Windows test
tasks.  It has been revamped to consistently skip revisions that
have already been tested, based on the tree object of the revision.

* js/ci-ghwf-dedup-tests:
  ci: do not skip tagged revisions in GitHub workflows
  ci: skip GitHub workflow runs for already-tested commits/trees

diff --cc .github/workflows/main.yml
Simple merge