ci: enable gh actions to read PR information

This is needed by amann/action-semantic-pull-request to validate
the PR title against Conventional Commit syntax rules.

Author: seansica

.github/workflows/ci.yml

@@ -8,6 +8,7 @@ on:
 
 permissions:
   contents: read
+  pull-requests: read
 
 jobs:
   # For PRs, validate the PR title (which becomes the squash commit message).