Only run builds on "push" events for v* test branch

[potiuk]

We do not need to run separate build on push and pull request when we are cherry-picking and pushing branch to apache/airflow repo. Those PRs are always made by committers, and they are done as direct push to the apache/airflow repo so they will run build on push (which will be equivalent of canary run). We also do not need to run anything on stable, because stable is the result of merging those changes from test after they get green.

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[potiuk]

This one will avoid running two builds (one for push and one for pull_request) when we are working on *test branch.

[potiuk]

Another finding from 2.6.2 preparation

[potiuk]

This likely led to "permission error" when two builds at teh same time tried to push the same image in v2-6-test branch

[jedcunningham]

We also do not need to run anything on stable, because stable is the result of merging those changes from test after they get green.

Doesn't the run on stable update constraint files though?

[potiuk]

We also do not need to run anything on stable, because stable is the result of merging those changes from test after they get green.

Doesn't the run on stable update constraint files though?

Glad you asked :)

Nope. The "v*-test" one updates constraints immediately if the test build succeeds. We do not need to defer updating constraints - this is only needed for PR runs (the reason why we do not update constraints for PRs is that they will break other's PRs if pushed too early).

This is controlled by "canary-run" flag, which is set by "get-workflow-info":

    def is_canary_run(self) -> str:
        if (
            self.event_name == "push"
            and self.head_repo == "apache/airflow"
            and self.ref_name
            and (self.ref_name == "main" or TEST_BRANCH_MATCHER.match(self.ref_name))
        ):
            return "true"
        return "false"