Remove "Require symfony/flex" step from tests

Author: rosier

.github/workflows/tests.yaml

@@ -58,9 +58,6 @@ jobs:
                   key: ${{ runner.os }}-${{ matrix.php-version }}-composer-${{ hashFiles('composer.json') }}
                   restore-keys: ${{ runner.os }}-${{ matrix.php-version }}-composer-
 
-            - name: "Require symfony/flex"
-              run: composer require --no-progress --no-scripts --no-plugins symfony/flex
-
             - name: "Install dependencies"
               run: composer update --no-interaction --prefer-dist --optimize-autoloader