Added phpcs to GitHub build action

Author: robtimus

.github/workflows/build.yml

@@ -47,6 +47,30 @@ jobs:
       - name: PHPStan
         run: phpstan analyse
 
+  phpcs:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          persist-credentials: false
+      - name: Set up PHP 8.2
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: '8.2'
+          tools: phpcs
+      - name: Cache Composer packages
+        id: composer-cache
+        uses: actions/cache@v4
+        with:
+          path: vendor
+          key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-php-
+      - name: Install dependencies
+        run: composer install -q --no-ansi --no-interaction --no-scripts --no-progress --prefer-dist
+      - name: PHPCS
+        run: phpcs src
+
   test:
     runs-on: ubuntu-latest
     strategy: