Simplify github action

Author: franmomu

.github/workflows/continuous-integration.yaml

@@ -32,22 +32,24 @@ jobs:
     runs-on: 'ubuntu-20.04'
     name: 'PHPUnit (PHP ${{ matrix.php }}, ES ${{ matrix.elasticsearch }})'
     timeout-minutes: 10
+    env:
+      SYMFONY_REQUIRE: "${{ matrix.symfony_require }}"
     strategy:
       matrix:
         include:
           - php: '7.2'
             elasticsearch: '7.0.0'
-            composer_flags: '--prefer-lowest --prefer-stable'
+            dependencies: 'lowest'
             symfony_require: '4.4.*'
           - php: '7.3'
             elasticsearch: '7.4.0'
-            composer_flags: '--prefer-stable'
+            dependencies: 'highest'
           - php: '7.4'
             elasticsearch: '7.9.0'
-            composer_flags: '--prefer-stable'
+            dependencies: 'highest'
           - php: '8.0'
             elasticsearch: '7.11.0'
-            composer_flags: '--prefer-stable'
+            dependencies: 'highest'
       fail-fast: false
     steps:
       - name: 'Checkout'
@@ -61,26 +63,14 @@ jobs:
           tools: 'pecl, composer:v2'
           extensions: 'curl, json, mbstring, mongodb-1.9.0, openssl'
 
-      - name: 'Get composer cache directory'
-        id: 'composer_cache'
-        run: |
-          echo "::set-output name=dir::$(composer config cache-files-dir)"
+      - name: "Globally install symfony/flex"
+        run: "composer global require --no-progress --no-scripts --no-plugins symfony/flex"
 
-      - name: 'Cache dependencies'
-        uses: 'actions/cache@v2'
+      - name: "Install Composer dependencies (${{ matrix.dependencies }})"
+        uses: "ramsey/composer-install@v1"
         with:
-          path: '${{ steps.composer_cache.outputs.dir }}'
-          key: '${{ runner.os }}-composer-php${{ matrix.php }}-${{ hashFiles(''**/composer.json'') }}'
-          restore-keys: |
-            ${{ runner.os }}-composer-php${{ matrix.php }}-
-            ${{ runner.os }}-composer-
-
-      - name: 'Update dependencies'
-        env:
-          SYMFONY_REQUIRE: "${{ matrix.symfony_require }}"
-        run: |
-          composer global require --no-progress --no-scripts --no-plugins symfony/flex
-          composer update --prefer-dist --no-interaction --no-progress --ansi ${{ matrix.composer_flags }}
+            dependency-versions: "${{ matrix.dependencies }}"
+            composer-options: "--prefer-dist --prefer-stable"
 
       - name: 'Setup Elasticsearch'
         run: |