Fix PR artifacts workflow - add pull-requests write permission

Co-authored-by: kevinelliott <123112+kevinelliott@users.noreply.github.com>

Author: Copilot

.github/workflows/build-pr.yml

@@ -4,6 +4,10 @@ on:
   pull_request:
     types: [opened, synchronize, reopened]
 
+permissions:
+  contents: read
+  pull-requests: write
+
 jobs:
   build-pr:
     name: Build PR Artifacts