Fix PHPStan workflow

.github/workflows/extdn-phpstan.yml

@@ -1,14 +1,27 @@
 name: ExtDN M2 PHPStan
-on: [push, pull_request]
+on: [ push, pull_request ]
 
 jobs:
   phpstan:
     name: M2 PHPStan
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: extdn/github-actions-m2/magento-phpstan@master
+
+      - name: "Determine composer cache directory"
+        id: "determine-composer-cache-directory"
+        run: "echo \"::set-output name=directory::$(composer config cache-dir)\""
+
+      - name: Cache Composer dependencies
+        uses: actions/cache@v2
+        with:
+          path: "${{ steps.determine-composer-cache-directory.outputs.directory }}"
+          #path: /tmp/composer-cache
+          key: ${{ runner.os }}-${{ hashFiles('**/composer.lock') }}
+
+      - uses: extdn/github-actions-m2/magento-phpstan/8.3@master
         with:
-          composer_name: ${{ secrets.COMPOSER_NAME }}
-    env:
-      MAGENTO_PRE_INSTALL_SCRIPT: .github/workflows/extdn-integration-tests-pre-install.sh
+          composer_name: yireo/magento2-webp2
+          composer_version: 2
+          phpstan_level: 2
+          magento_pre_install_script: .github/workflows/extdn-integration-tests-pre-install.sh