github actions: skip JIRA checks if secrets are unavailable

There are many workflows that are useful without the JIRA checks from
Forks.  We're still evaluating how to best deal with this without a lot
of engineer overhead to check extrenal contributors.

Author: PlaidCat

.github/workflows/validate-kernel-commits.yml

@@ -171,6 +171,7 @@ jobs:
           JIRA_API_USER: ${{ secrets.JIRA_API_USER }}
           JIRA_URL: ${{ secrets.JIRA_URL }}
         working-directory: kernel-src-tree-tools
+        if: ${{ JIRA_API_TOKEN != '' && JIRA_API_USER != '' && JIRA_URL != '' }} # Only run if JIRA creds are set
         run: |
           # Run script and capture output, ensuring credentials are never echoed
           set +x  # Disable command echo to prevent credential exposure