rm merge-dependabot-pr.yml from Unsupported Branch

.github/workflows/merge-dependabot-pr.yml

@@ -1,63 +0,0 @@
-name: Merge Dependabot PR
-
-on: pull_request_target
-
-run-name: Merge Dependabot PR ${{ github.ref_name }}
-
-permissions: write-all
-
-jobs:
-  merge-dependabot-pr:
-    name: Merge Dependabot PR
-    runs-on: ubuntu-latest
-    if: ${{ github.event.pull_request.user.login == 'dependabot[bot]' && github.repository == 'spring-projects/spring-security' }}
-    steps:
-
-      - uses: actions/checkout@v4
-        with:
-          show-progress: false
-          ref: ${{ github.event.pull_request.head.sha }}
-
-      - uses: actions/setup-java@v4
-        with:
-          distribution: temurin
-          java-version: 17
-
-      - name: Set Milestone to Dependabot Pull Request
-        id: set-milestone
-        run: |
-          if test -f pom.xml
-          then
-            CURRENT_VERSION=$(mvn help:evaluate -Dexpression="project.version" -q -DforceStdout)
-          else
-            CURRENT_VERSION=$(cat gradle.properties | sed -n '/^version=/ { s/^version=//;p }')
-          fi
-          export CANDIDATE_VERSION=${CURRENT_VERSION/-SNAPSHOT}
-          MILESTONE=$(gh api repos/$GITHUB_REPOSITORY/milestones --jq 'map(select(.due_on != null and (.title | startswith(env.CANDIDATE_VERSION)))) | .[0] | .title')
-          
-          if [ -z $MILESTONE ]
-          then
-            gh run cancel ${{ github.run_id }}
-            echo "::warning title=Cannot merge::No scheduled milestone for $CURRENT_VERSION version"
-          else
-            gh pr edit ${{ github.event.pull_request.number }} --milestone $MILESTONE
-            echo mergeEnabled=true >> $GITHUB_OUTPUT
-          fi
-        env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-
-      - name: Merge Dependabot pull request
-        if: steps.set-milestone.outputs.mergeEnabled
-        run: gh pr merge ${{ github.event.pull_request.number }} --auto --rebase
-        env:
-          GH_TOKEN: ${{ secrets.GH_ACTIONS_REPO_TOKEN }}
-  send-notification:
-    name: Send Notification
-    needs: [ merge-dependabot-pr ]
-    if: ${{ failure() || cancelled() }}
-    runs-on: ubuntu-latest
-    steps:
-      - name: Send Notification
-        uses: spring-io/spring-security-release-tools/.github/actions/send-notification@v1
-        with:
-          webhook-url: ${{ secrets.SPRING_SECURITY_CI_GCHAT_WEBHOOK_URL }}