Update minimal version in tests

Author: Lustmored

.github/workflows/test.yaml

@@ -23,7 +23,7 @@ jobs:
             - uses: actions/checkout@master
             - uses: shivammathur/setup-php@v2
               with:
-                  php-version: '7.1'
+                  php-version: '7.2'
             - name: PHPUnit
               run: |
                   composer require --no-update symfony/config=$SYMFONY_VERSION symfony/http-kernel=$SYMFONY_VERSION symfony/dependency-injection=$SYMFONY_VERSION symfony/options-resolver=$SYMFONY_VERSION