message: trivial - remove extraneous cancelablePromise
  This looks like it was just left behind and it generates a lot of console errors
diff: @@ -162,8 +162,6 @@ export default class SummaryPanelGraph extends React.Component<SummaryPanelPropT
  });
  });
  - this.metricsPromise = makeCancelablePromise(promise);
  -
  this.setState({ loading: true, metricsLoadError: null });
  };
  