fix: grant contents:write to buildassets job in release flow (#732)

The build_assets.yml reusable workflow now declares contents:write (needed
to attach release assets via upload-release-action). A called workflow cannot
request more permission than the caller grants, so release_flow.yml calling
it with only contents:read caused a startup_failure. Grant contents:write on
the buildassets job so the reusable workflow can compile and upload assets.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: thomasrockhu-codecov

.github/workflows/release_flow.yml

@@ -21,6 +21,8 @@ jobs:
 
   buildassets:
     name: Build packages
+    permissions:
+      contents: write # required so the reusable workflow can attach release assets
     uses: ./.github/workflows/build_assets.yml
     with:
       release: true