fixup! ci: check fixup commits are autosquashed before PR merge

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

Author: matejchalk

.github/workflows/git-checks.yml

@@ -5,6 +5,8 @@ on: pull_request
 jobs:
   block-fixup:
     name: Block fixup commits
+    permissions:
+      contents: read
     runs-on: ubuntu-latest
     steps:
       - name: Clone repository