Update CI file

.github/workflows/ci.yml

@@ -69,7 +69,7 @@ jobs:
           bash -c 'response=0; while [ $response -ne 200 ]; do sleep 1; response=$(curl --write-out %{http_code} --silent --output /dev/null http://localhost:12800/receiveData);echo $response;done'
 
       - name: Publish Dokcer image
-        if: matrix.php-versions == '7.4' && github.ref == 'master'
+        if: matrix.php-versions == '7.4' && github.event == 'push'
         uses: elgohr/Publish-Docker-Github-Action@2.13
         with: 
           name: skyapm/skywalking-php