[CI] Change verify_default_branch job name to "In-tree build"

Motivation: use the name as check in "Require status checks to pass".
The name should be the same for all branches.

.github/workflows/on-push-verification.yml

@@ -28,7 +28,7 @@ on:
 jobs:
 
   verify_default_branch:
-    name: Verify for `main` branch
+    name: In-tree build
     # ref_name for 'on: push'
     # base_ref for 'on: pull_request'
     if: ${{ (github.event_name == 'push' && github.ref_name == 'main') || (github.event_name == 'pull_request' && github.base_ref == 'main') }}