gate on apache repo

Author: kevinjqliu

.github/workflows/nightly-pypi-build.yml

@@ -26,6 +26,7 @@ on:
 
 jobs:
   set-version:
+    if: github.repository == 'apache/iceberg-python'  # Only run for apache repo
     runs-on: ubuntu-latest
     outputs:
       VERSION: ${{ steps.set-version.outputs.VERSION }}