Bump korthout/backport-action from 2 to 4.4.0 (#5597)

* Bump korthout/backport-action from 2 to 4.4.0

Bumps [korthout/backport-action](https://github.com/korthout/backport-action) from 2 to 4.4.0.
- [Release notes](https://github.com/korthout/backport-action/releases)
- [Commits](korthout/backport-action@v2...v4.4.0)

---
updated-dependencies:
- dependency-name: korthout/backport-action
  dependency-version: 4.4.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

* Update backport-action to version 4

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Tim Donohue <tim.donohue@lyrasis.org>

Author: dependabot[bot]

.github/workflows/port_merged_pull_request.yml

@@ -27,7 +27,7 @@ jobs:
       # Port PR to other branch (ONLY if labeled with "port to")
       # See https://github.com/korthout/backport-action
       - name: Create backport pull requests
-        uses: korthout/backport-action@v2
+        uses: korthout/backport-action@v4
         with:
           # Trigger based on a "port to [branch]" label on PR
           # (This label must specify the branch name to port to)
@@ -43,4 +43,4 @@ jobs:
           merge_commits: 'skip'
           # Use a personal access token (PAT) to create PR as 'dspace-bot' user.
           # A PAT is required in order for the new PR to trigger its own actions (for CI checks)
-          github_token: ${{ secrets.PR_PORT_TOKEN }}
+          github_token: ${{ secrets.PR_PORT_TOKEN }}