Trigger the docs deploy job only when GH_PAGES_DEPLOY secret is set.

This is to avoid a forked repo triggering this job which is deemed to fail.

Author: badmonster0

.github/workflows/docs.yml

@@ -5,6 +5,7 @@ on:
     branches: [main]
     paths:
       - docs/**
+      - **/*.yml
   push:
     branches: [main]
     paths:
@@ -38,7 +39,7 @@ jobs:
         run: yarn build
 
   deploy:
-    if: github.event_name != 'pull_request'
+    if: ${{ github.event_name != 'pull_request' && github.secrets.GH_PAGES_DEPLOY != '' }}
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4