chore: Update cron timing and add concurrency control to label update workflow

Author: snovak7

.github/workflows/cron-update-labels.yml

@@ -4,7 +4,7 @@ on:
   # Manually run the job
   workflow_dispatch:
   # Periodically run the job
-  # Every first day of the month at 1:27 UTC
+  # Every first day of the month at 1:28 UTC
   schedule:
     - cron: "28 1 1 * *"
 
@@ -13,6 +13,11 @@ permissions:
   contents: read
   issues: write
 
+# Prevent Concurrent Jobs
+concurrency:
+  group: labels-monthly-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   # Runs reusable workflow (utility-update-labels.yml on the main branch) from keystone repository
   create-labels: