refactor: remove useBillingAndUsageData hook

packages/backend/src/graphql/query-resolvers.js

@@ -1,6 +1,5 @@
 import getApp from './queries/get-app.js';
 import getAppAuthClient from './queries/get-app-auth-client.ee.js';
-import getBillingAndUsage from './queries/get-billing-and-usage.ee.js';
 import getConnectedApps from './queries/get-connected-apps.js';
 import getDynamicData from './queries/get-dynamic-data.js';
 import getStepWithTestExecutions from './queries/get-step-with-test-executions.js';
@@ -9,7 +8,6 @@ import testConnection from './queries/test-connection.js';
 const queryResolvers = {
   getApp,
   getAppAuthClient,
-  getBillingAndUsage,
   getConnectedApps,
   getDynamicData,
   getStepWithTestExecutions,