Merge pull request #28706 from nextcloud/backport/28700/stable21

[stable21] Pin Psalm version for security analysis

Author: LukasReschke

.github/workflows/psalm-security.yml

@@ -16,7 +16,7 @@ jobs:
         with:
           submodules: recursive
       - name: Psalm
-        uses: docker://vimeo/psalm-github-actions
+        uses: docker://vimeo/psalm-github-actions:4.9.3
         with:
           security_analysis: true
           report_file: results.sarif