ci: add push codeql trigger

Author: robert-hebel-sb

.github/workflows/codeql.yml

@@ -13,7 +13,9 @@ name: "CodeQL"
 
 on:
   pull_request:
-    branches: [ master ]
+    branches: [ "master" ]
+  push:
+    branches: [ "master" ]
   schedule:
     - cron: '16 04 * * 2'