use the right working-directory

Author: rvanlaak

.github/workflows/static-code-analysis.yml

@@ -1,6 +1,6 @@
 name: Static code analysis
 
-on: [push,pull_request]
+on: [pull_request]
 
 jobs:
   static-code-analysis:
@@ -10,4 +10,4 @@ jobs:
       - name: Run PHPStan
         uses: docker://jakzal/phpqa:php7.3-alpine
         with:
-            args: phpstan analyze
+            args: "phpstan analyze ${GITHUB_WORKSPACE}"