In release.yml

  - in publish-pypi job,
    - only proceed if there are python packages to publish

  - in publish-npm job,
        - only proceed if there are npm packages to publish

Author: cliffhall

.github/workflows/release.yml

@@ -104,6 +104,7 @@ jobs:
 
   publish-pypi:
     needs: [update-packages, create-metadata]
+    if: ${{ needs.create-metadata.outputs.pypi_packages != '[]' && needs.create-metadata.outputs.pypi_packages != '' }}
     strategy:
       fail-fast: false
       matrix:
@@ -145,6 +146,7 @@ jobs:
 
   publish-npm:
     needs: [update-packages, create-metadata]
+    if: ${{ needs.create-metadata.outputs.npm_packages != '[]' && needs.create-metadata.outputs.npm_packages != '' }}
     strategy:
       fail-fast: false
       matrix: