switch to default composer

.github/workflows/ci.yml

@@ -61,19 +61,21 @@ jobs:
         extensions: ${{ env.PHP_EXTENSIONS }}
         ini-values: ${{ env.PHP_INI_VALUES }}
 
-      - name: Determine composer cache directory
+    - name: Validate composer.json and composer.lock
-        run: echo "COMPOSER_CACHE_DIR=$(./tools/composer config cache-dir)" >> $GITHUB_ENV
+      run: composer validate
 
-      - name: Cache dependencies installed with composer
+    - name: Cache Composer packages
+      id: composer-cache
       uses: actions/cache@v2
       with:
-          path: ${{ env.COMPOSER_CACHE_DIR }}
+        path: vendor
-          key: php${{ matrix.php-version }}-composer-${{ hashFiles('**/composer.json') }}
+        key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
         restore-keys: |
-            php${{ matrix.php-version }}-composer-
+          ${{ runner.os }}-php-
 
-      - name: Install dependencies with composer
+    - name: Install dependencies
-        run: php ./tools/composer update --no-ansi --no-interaction --no-progress
+      if: steps.composer-cache.outputs.cache-hit != 'true'
+      run: composer install --prefer-dist --no-progress --no-suggest
 
     - name: Run tests with phpunit
       run: ./phpunit.sh