Update delete_backport_branch workflow to include release-chores branches

Signed-off-by: Riley Jerger <rjerger@amazon.com>

Author: RileyJergerAmazon

.github/workflows/delete_backport_branch.yml

@@ -7,7 +7,7 @@ on:
 jobs:
   delete-branch:
     runs-on: ubuntu-latest
-    if: startsWith(github.event.pull_request.head.ref,'backport/')
+    if: startsWith(github.event.pull_request.head.ref,'backport/') || startsWith(github.event.pull_request.head.ref,'release-chores/')
     steps:
       - name: Delete merged branch
         uses: SvanBoxel/delete-merged-branch@main