Fix CI (#2654)

framework/core/.github/workflows/test.yml

@@ -8,7 +8,7 @@ jobs:
 
     strategy:
       matrix:
-        php: [7.2, 7.3, 7.4, '8.0']
+        php: ['7.2', '7.3', '7.4', '8.0']
         service: ['mysql:5.7', mariadb]
         prefix: ['', flarum_]
 
@@ -51,13 +51,22 @@ jobs:
     steps:
       - uses: actions/checkout@master
 
-      - name: Select PHP version
+      - name: Setup PHP
-        run: sudo update-alternatives --set php $(which php${{ matrix.php }})
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          coverage: xdebug
+          extensions: curl, dom, gd, json, mbstring, openssl, pdo_mysql, tokenizer, zip
+          tools: phpunit, composer:v2
 
+      # The authentication alter is necessary because newer mysql versions use the `caching_sha2_password` driver,
+      # which isn't supported prior to PHP7.4
+      # When we drop support for PHP7.3, we should remove this from the setup.
       - name: Create MySQL Database
         run: |
           sudo systemctl start mysql
           mysql -uroot -proot -e 'CREATE DATABASE flarum_test;' --port 13306
+          mysql -uroot -proot -e "ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'root';" --port 13306
 
       - name: Install Composer dependencies
         run: composer install