enable CI on all PRs

Co-authored-by: Agustín Borgna <[email protected]>

.github/workflows/ci-rs.yml

@@ -4,10 +4,9 @@ on:
   push:
     branches:
       - main
-      - doug/init-hugr-llvm-subtree # remove before merging
   pull_request:
     branches:
-      - main
+      - '*'
   merge_group:
     types: [checks_requested]
   workflow_dispatch: {}