Correct yml syntax

Author: bbimber

.github/workflows/sync-repos.yml

@@ -4,6 +4,7 @@ on:
     - cron:  "10 */3 * * *"
 jobs:
   sync-release-branches:
+    if: github.head_ref == ""
     runs-on: ubuntu-latest
     steps:
       - name: "Sync Release Branches"
@@ -15,6 +16,7 @@ jobs:
           destination_branch_prefix: "discvr-"
           github_token: ${{ secrets.GITHUB_TOKEN }}
   sync-develop:
+    if: github.head_ref == ""
     runs-on: ubuntu-latest
     steps:
       - name: "Sync Develop Branch"