push docker image to gcr

.github/workflows/release-slackbot-proxy.yml

@@ -33,6 +33,12 @@ jobs:
         username: wsmoogle
         password: ${{ secrets.DOCKER_REGISTRY_ON_GITHUB_PASSWORD }}
 
+    -name: Setup gcloud
+      uses: GoogleCloudPlatform/github-actions/setup-gcloud@master
+      with:
+        service_account_key: ${{ secrets.GCP_SA_KEY_SLACKBOT_PROXY }}
+        export_default_credentials: true
+
     - name: Build and push
       uses: docker/build-push-action@v2
       working-directory: ./packages/slackbot-proxy
@@ -46,6 +52,8 @@ jobs:
           weseek/growi-slackbot-proxy:${{ env.RELEASE_VERSION }}
           ghcr.io/weseek/growi-slackbot-proxy:latest
           ghcr.io/weseek/growi-slackbot-proxy:${{ env.RELEASE_VERSION }}
+          asia.gcr.io/${{ env.GCP_PRJ_ID_SLACKBOT_PROXY }}/growi-slackbot-proxy:latest
+          asia.gcr.io/${{ env.GCP_PRJ_ID_SLACKBOT_PROXY }}/growi-slackbot-proxy:${{ env.RELEASE_VERSION }}
 
     - name: Update Docker Hub Description
       uses: peter-evans/dockerhub-description@v2