Add comment explaining fetch-depth: 0 requirement for lookup-run-id script

Co-authored-by: leofang <5534781+leofang@users.noreply.github.com>

Author: Copilot

.github/workflows/release.yml

@@ -52,6 +52,7 @@ jobs:
       - name: Checkout Source
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8  # v5.0.0
         with:
+          # fetch-depth: 0 is required so the lookup-run-id script can access all git tags
           fetch-depth: 0
 
       - name: Determine Run ID