Changes

chore(tekton/v0): update triggers to match branches for tidb-operator repo (#3902)

This pull request updates the branch filtering logic in the
`git-push.yaml` Tekton trigger for the `tidb-operator` repository. The
change ensures that only pushes to the `main` branch and branches
matching `release-*` trigger the pipeline, and removes support for the
`master` and `feature/v2` branches.

Branch filtering update:

* Updated the `body.ref.matches` regular expression to trigger only on
`main` and `release-*` branches, removing `master` and `feature/v2` from
the allowed branches in `git-push.yaml`.
 (commit: 5e8803d)