github: Fix publishing packages when updating an open PR.

Author: projectgus

.github/workflows/build_packages.yml

@@ -18,7 +18,7 @@ jobs:
     - name: Compile package index
       run: source tools/ci.sh && ci_build_packages_compile_index
     - name: Publish packages for branch
-      if: vars.MICROPY_PUBLISH_MIP_INDEX && github.event_name == 'push' && ! github.event.deleted
+      if: vars.MICROPY_PUBLISH_MIP_INDEX && ! github.event.deleted
       run: source tools/ci.sh && ci_push_package_index
     - name: Upload packages as artifact
       uses: actions/upload-artifact@v3