Run backport action when creating PR

.github/workflows/backport-check.yml

@@ -1,29 +0,0 @@
-# Copyright 2022 Signal Messenger, LLC
-# SPDX-License-Identifier: AGPL-3.0-only
-name: Backport Check
-on:
-  pull_request:
-    types: [opened, labeled]
-jobs:
-  backport-check:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Check pull request has a backport label
-        env:
-          EVENT_ACTION: ${{ github.event.action }}
-          EVENT_LABEL_NAME: ${{ toJSON(github.event.label.name) }}
-          EVENT_PULL_REQUEST_LABELS: ${{ toJSON(github.event.pull_request.labels.*.name) }}
-        shell: bash
-        run: |
-          LABELS="$EVENT_PULL_REQUEST_LABELS, $EVENT_LABEL_NAME"
-          BACKPORT_LABELS="backport no-backport needs-backport needs-manual-backport"
-          echo "Found labels: $LABELS"
-          for BACKPORT_LABEL in $BACKPORT_LABELS; do
-            echo "Checking for label '$BACKPORT_LABEL'"
-            if echo "$LABELS" | grep -q "\"$BACKPORT_LABEL\""; then
-              echo "Has '$BACKPORT_LABEL' label"
-              exit 0
-            fi
-          done
-          echo "Does not have any backport label"
-          exit 1

.github/workflows/backport.yml

@@ -6,7 +6,7 @@ on:
   issue_comment:
     types: [created]
   pull_request:
-    types: [closed]
+    types: [opened, labeled, unlabeled, closed]
 
 jobs:
   backport: