.github: Bump korthout/backport-action from 4.5.0 to 4.5.1

Bumps [korthout/backport-action](https://github.com/korthout/backport-action) from 4.5.0 to 4.5.1.
- [Release notes](https://github.com/korthout/backport-action/releases)
- [Commits](https://github.com/korthout/backport-action/compare/7c3f6cd5843cac11bc59a04a1b7699af93261670...bf97bcfb53d5250af8b9a15fab0f56158a63b224)

---
updated-dependencies:
- dependency-name: korthout/backport-action
  dependency-version: 4.5.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/backport.yml

@@ -49,7 +49,7 @@ jobs:
 
       - name: Create backport PRs
         id: backport
-        uses: korthout/backport-action@7c3f6cd5843cac11bc59a04a1b7699af93261670 # v4.5.0
+        uses: korthout/backport-action@bf97bcfb53d5250af8b9a15fab0f56158a63b224 # v4.5.1
         with:
           # Config README: https://github.com/korthout/backport-action#backport-action
           add_author_as_reviewer: true