ci: only publish python package and docker image on release

.github/workflows/build.yml

@@ -86,6 +86,7 @@ jobs:
         run: python -m build
 
       - name: Publish Python package
+        if: github.event_name == 'release'
         env:
           PYPI_USERNAME: ${{ secrets.PYPI_USERNAME }}
           PYPI_PASSWORD: ${{ secrets.PYPI_PASSWORD }}
@@ -102,12 +103,14 @@ jobs:
         uses: docker/setup-buildx-action@v2
 
       - name: Login to DockerHub
+        if: github.event_name == 'release'
         uses: docker/login-action@v2
         with:
           username: ${{ secrets.DOCKER_USERNAME }}
           password: ${{ secrets.DOCKER_PASSWORD }}
 
       - name: Login to GitHub Container Registry
+        if: github.event_name == 'release'
         uses: docker/login-action@v2
         with:
           registry: ghcr.io
@@ -146,6 +149,6 @@ jobs:
         uses: docker/build-push-action@v3
         with:
           context: .
-          push: true
+          push: ${{ github.event_name == 'release' }}
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}