[skip ci] Readme: Add Github Actions nightly workflow status badge

Author: Ayesh

README.md

@@ -17,6 +17,7 @@ blog to the most popular websites in the world. PHP is distributed under the
 [![Build status](https://travis-ci.com/php/php-src.svg?branch=master)](https://travis-ci.com/github/php/php-src)
 [![Build status](https://ci.appveyor.com/api/projects/status/meyur6fviaxgdwdy/branch/master?svg=true)](https://ci.appveyor.com/project/php/php-src)
 [![Build Status](https://dev.azure.com/phpazuredevops/php/_apis/build/status/php.php-src?branchName=master)](https://dev.azure.com/phpazuredevops/php/_build/latest?definitionId=1&branchName=master)
+[![Push](https://github.com/php/php-src/actions/workflows/push.yml/badge.svg)](https://github.com/php/php-src/actions/workflows/push.yml)
 [![Fuzzing Status](https://oss-fuzz-build-logs.storage.googleapis.com/badges/php.svg)](https://bugs.chromium.org/p/oss-fuzz/issues/list?sort=-opened&can=1&q=proj:php)
 
 ## Documentation