FIX: return 429 when admin api key is limited on admin route

This also handles a general case where exceptions leak out prior to being handled by the application controller

spec/requests/admin/admin_controller_spec.rb

@@ -2,8 +2,7 @@ require 'rails_helper'
 
 RSpec.describe Admin::AdminController do
   it "should return the right response if user isn't a staff" do
-    expect do
-      get "/admin", params: { api_key: 'asdiasiduga' }
-    end.to raise_error(ActionController::RoutingError)
+    get "/admin", params: { api_key: 'asdiasiduga' }
+    expect(response.status).to eq(404)
   end
 end