ci: run gitea action from PR mutally exclusive to push

Run-Checks

.gitea/workflows/ci.yml

@@ -8,8 +8,11 @@ on:
 jobs:
   run-ci-linux:
     runs-on: ubuntu-latest
+    # run action mutally exclusive on PRs or
+    # push with commit containing "Run-Checks"
     if: >
-      contains(github.event.head_commit.message, 'Run-Checks') ||
+      (contains(github.event.head_commit.message, 'Run-Checks') &&
+      github.event_name == 'push') ||
       github.event_name == 'pull_request'
     steps:
       - name: Check out repository code