refactor(core): Use Response(status=404) instead of make_response

Cleaner solution for returning 404 in the dashboard access denial case:
- Response(status=404) returns an empty response with proper status
- Simpler than make_response('Not Found', 404)
- Lets browser/client handle 404 appropriately
- All tests still pass

Co-Authored-By: Claude <[email protected]>

Author: mistercrunch

superset/views/core.py

@@ -29,7 +29,6 @@
     abort,
     current_app as app,
     g,
-    make_response,
     redirect,
     request,
     Response,
@@ -770,7 +769,7 @@ def dashboard(
             dashboard.raise_for_access()
         except SupersetSecurityException:
             # Return 404 to avoid revealing dashboard existence
-            return make_response("Not Found", 404)
+            return Response(status=404)
         add_extra_log_payload(
             dashboard_id=dashboard.id,
             dashboard_version="v2",