feat: Add retest workflow. Fixes #12864

Signed-off-by: Miltiadis Alexis <[email protected]>

.github/workflows/retest.yaml

@@ -0,0 +1,24 @@
+name: Detect and Trigger Retest
+on:
+  issue_comment:
+    types: [created, edited]
+
+permissions:
+  contents: read
+
+jobs:
+  retest:
+    runs-on: ubuntu-latest
+    if: github.event.comment.author_association == 'MEMBER' && github.event.comment.body == '/retest'
+    permissions:
+      actions: write
+    steps:
+      - name: Retest
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          REPO: ${{ github.repository }}
+          PR_NUMBER: ${{ github.event.issue.number }}
+        run: |
+          SHA_REF=$(gh api "/repos/$REPO/pulls/$PR_NUMBER/commits?per_page=1" | jq -r '.[].sha')
+          RUN_ID=$(gh api "repos/$REPO/actions/workflows/ci-build.yaml/runs?per_page=1&event=pull_request&head_sha=$SHA_REF" | jq -r '.workflow_runs[] | .id')
+          gh api --method POST repos/$REPO/actions/runs/$RUN_ID/rerun-failed-jobs