Revert "ci: Upgrade github-script action to version 8 (#54726)"

This reverts commit 0cd0b8213d.

.github/workflows/propogate-auto-merge.yml

@@ -15,7 +15,7 @@ jobs:
     steps:
       - name: Detect backport and original PR (metadata)
         id: extract
-        uses: actions/github-script@v8
+        uses: actions/github-script@v7
         with:
           script: |
             const pr = context.payload.pull_request;
@@ -67,4 +67,4 @@ jobs:
               repo: context.repo.repo,
               issue_number: context.payload.pull_request.number,
               labels: ["auto-merge"]
-            });
+            });