Run rector-php-cs-fixer-pr job only on PR-s (#28)

@mkrauser This will not fail on pushes.

.github/workflows/ci.yml

@@ -87,7 +87,7 @@ jobs:
   rector-php-cs-fixer-pr:
     name: PHP-CS-Fixer / Rector
     runs-on: "ubuntu-latest"
-    if: github.actor != 'dependabot[bot]'
+    if: github.actor != 'dependabot[bot]' && github.event_name == 'pull_request'
     steps:
       - name: "Checkout"
         uses: "actions/checkout@v4"
@@ -149,4 +149,4 @@ jobs:
           commit-message: Changed by rector in ${{ steps.pr.outputs.branch }}
       - name: Fail the workflow when necessary CS fixes were detected
         run: echo "Failing workflow run because CS violations were detected." && exit 1
-        if: steps.create-pull-request.outputs.pr_number
+        if: steps.create-pull-request.outputs.pr_number