add lint check with GitHub Actions

.github/workflows/lint.yml

@@ -0,0 +1,22 @@
+name: Lint
+on:
+  push:
+    branches:
+      - master
+      - stable*
+  pull_request:
+
+jobs:
+  lint-php:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+    - name: Install Dependencies
+      run: composer install --prefer-dist
+    - name: Load problem matcher for php -l
+      uses: korelstar/phplint-problem-matcher@v1
+    - name: PHP syntax check
+      run: "find src/ -type f -name '*.php' -print0 | xargs -0 -L1 -P4 -- php -l -f"
+    - name: PHP Coding Standards Fixer
+      run: vendor/bin/php-cs-fixer fix --dry-run --diff

.php_cs.dist

@@ -4,10 +4,12 @@ declare(strict_types=1);
 
 require_once './vendor/autoload.php';
 
-use ChristophWurst\Nextcloud\CodingStandard\Config;
+use Nextcloud\CodingStandard\Config;
 
 $config = new Config();
 $config
 	->getFinder()
+	->ignoreVCSIgnored(true)
+	->notPath('vendor')
 	->in(__DIR__);
 return $config;