run composer from docker instead of local

.github/workflows/main.yml

@@ -9,12 +9,12 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v2
 
-      - name: Composer Install
-        run: composer install --ignore-platform-reqs
-
       - name: Build Docker Container
         run: docker-compose -f docker-compose.yml build >/dev/null
 
+      - name: Composer Install
+        run: docker-compose -f docker-compose.yml run php composer install --ignore-platform-reqs -d /opt/project/phpstorm-stubs
+
       - name: Run Tests
         run: docker-compose -f docker-compose.yml run php /opt/project/phpstorm-stubs/vendor/bin/phpunit /opt/project/phpstorm-stubs/tests/
 
@@ -22,4 +22,4 @@ jobs:
         run: ./tests/check-stub-map
 
       - name: run cs fixer
-        run: composer cs
+        run: docker-compose -f docker-compose.yml run php composer cs -d /opt/project/phpstorm-stubs

CONTRIBUTING.md

@@ -9,7 +9,7 @@ Please check our [issue tracker] for issues corresponding to the problem you're
 * Please avoid any unnecessary changes e.g., spacing, line endings, HTML formatting. Remember, these files are NOT for human consumption. We want to preserve meaningful history.
 * Please try to match existing style for any particular file - formatting, spacing, naming conventions.
 * Please add corresponding @since tags
-* Please run `composer cs` to check the code style and `composer cs-fix` to fix it
+* Please run `docker-compose -f docker-compose.yml run php composer cs -d /opt/project/phpstorm-stubs` to check the code style and `docker-compose -f docker-compose.yml run php composer cs-fix -d /opt/project/phpstorm-stubs` to fix it
 
 ## Tests
  * Please make sure that tests pass for your Pull Request.