Revert ".github/workflows/sonar.yml: Temporarily enable in PRs for testing purposes"

This reverts commit 3e77d68.

Author: NightOwl888

.github/workflows/sonar.yml

@@ -18,7 +18,6 @@
 name: SonarCloud
 on:
   workflow_dispatch:
-  pull_request:
   push:
     branches:
       - master