Update to setup-php@v2

Author: marickvantuil

.github/workflows/run-tests.yml

@@ -48,7 +48,7 @@ jobs:
         uses: actions/checkout@v2
 
       - name: Setup PHP
-        uses: shivammathur/setup-php@v1
+        uses: shivammathur/setup-php@v2
         with:
           php-version: ${{ matrix.php }}
           extensions: mbstring, dom, fileinfo