Bump to stable php-setup

Author: jaapio

.github/workflows/push.yml

@@ -214,7 +214,7 @@ jobs:
       - uses: actions/checkout@master
 
       - name: Setup PHP
-        uses: shivammathur/setup-php@develop
+        uses: shivammathur/setup-php@v2
         with:
           php-version: 7.2
           extensions: blackfire