ci: check if inside work tree

Author: SkySails

.github/workflows/pr.yml

@@ -77,6 +77,8 @@ jobs:
           filter: blob:none
           persist-credentials: false
 
+      - run: git rev-parse --is-inside-work-tree
+
       - name: Create env file
         run: |
           echo NAVIGATION_DATA_SIGNED_URL=${{ secrets.NAVIGATION_DATA_SIGNED_URL }} >> .env