kie-kogito-examples#2052: Remove deprecated pr-backporting wf (#2054)

.github/workflows/pr-backporting.yml

@@ -1,40 +0,0 @@
-name: Pull Request Backporting
-
-on:
-  pull_request_target:
-    types: [closed, labeled]
-env:
-  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-
-jobs:
-  compute-targets:
-    if: ${{ github.event.pull_request.state == 'closed' && github.event.pull_request.merged }}
-    runs-on: ubuntu-latest
-    outputs:
-      target-branches: ${{ steps.set-targets.outputs.targets }}
-    env:
-      LABELS: ${{ toJSON(github.event.pull_request.labels) }}
-    steps:
-      - name: Set target branches
-        id: set-targets
-        uses: apache/incubator-kie-kogito-pipelines/.ci/actions/parse-labels@main
-        with:
-          labels: ${LABELS}
-  
-  backporting:
-    if: ${{ github.event.pull_request.state == 'closed' && github.event.pull_request.merged && needs.compute-targets.outputs.target-branches != '[]' }}
-    name: "[${{ matrix.target-branch }}] - Backporting"
-    runs-on: ubuntu-latest
-    needs: compute-targets
-    strategy:
-      matrix: 
-        target-branch: ${{ fromJSON(needs.compute-targets.outputs.target-branches) }}
-      fail-fast: false
-    env:
-      REVIEWERS: ${{ toJSON(github.event.pull_request.requested_reviewers) }}
-    steps:
-      - name: Backporting
-        uses: apache/incubator-kie-kogito-pipelines/.ci/actions/backporting@main
-        with:
-          target-branch: ${{ matrix.target-branch }}
-          additional-reviewers: ${REVIEWERS}