fix grafana errors not caught by tsdb-kit

src/services/query_service/grafana.ts

@@ -29,7 +29,8 @@ export class GrafanaQueryService extends QueryService {
     _.defaults(axiosQuery, query.schema);
 
     try {
-      return axios(axiosQuery);
+      const resp = await axios(axiosQuery);
+      return resp;
     } catch (e) {
       // TODO: seems like this error handler can be used for both Grafana and Direct queries
       const msg = `TSDB-kit: fail while request data: ${e.message}`;