Adds `scripts/generate_release_notes.sh` to produce a structured CHANGELOG.md starting point using the Kubernetes release-notes tool. It handles both minor and patch releases.
`RELEASE.md` is updated to reference the script and drop the manual instructions.
Version examples are updated from 2.x to 3.x.
The `check_release_notes` CI workflow is extended to also run on `release-*` branches in order for the script to catch commits added to the release note , and the PR template wording is tightened.
Signed-off-by: machine424 <ayoubmrini424@gmail.com>
