add comment when fall-through is intentional in a non-empty case body

.github/workflows/linter.yml

@@ -31,4 +31,4 @@ jobs:
         args: --profile --ignore-platform-reqs
 
     - name: Run Linter
-      run: ./vendor/bin/phpcs -p || true
+      run: ./vendor/bin/phpcs -p

src/Appwrite/Migration/Version/V13.php

@@ -319,7 +319,7 @@ class V13 extends Migration
                             return 'buckets.*.' . implode('.', $parts);
                         case 'files':
                             return 'buckets.*.' . $second . '.*.' . implode('.', $parts);
-                    }
+                    } // intentional fallthrough
                 case 'database':
                     $second = array_shift($parts);
                     switch ($second) {