message: Query Browser: Skip SeriesButton render if no series found
  Fixes a bug where the `SeriesButton` would be visible even though it has
  no corresponding series in the graph, which happens when the graph is
  not rendered due to the dataset being too big.
diff: @@ -246,7 +246,9 @@ const seriesButtonStateToProps = ({UI}: RootState, {index, labels}) => {
  const isDisabled = _.some(disabledSeries, s => _.isEqual(s, labels));
  if (!isDisabled) {
  const series = UI.getIn(['queryBrowser', 'queries', index, 'series']);
  - if (!_.isEmpty(series)) {
  + if (_.isEmpty(series)) {
  + return {colorIndex: null, isDisabled, isSeriesEmpty: true};
  + }
  const colorOffset = UI.getIn(['queryBrowser', 'queries'])
  .take(index)
  .filter(q => q.get('isEnabled'))
  @@ -255,11 +257,13 @@ const seriesButtonStateToProps = ({UI}: RootState, {index, labels}) => {
  const colorIndex = (colorOffset + seriesIndex) % colors.length;
  return {colorIndex, isDisabled};
  }
  - }
  return {colorIndex: null, isDisabled};
  };
  -const SeriesButton_: React.FC<SeriesButtonProps> = ({colorIndex, isDisabled, toggleSeries}) => {
  +const SeriesButton_: React.FC<SeriesButtonProps> = ({colorIndex, isDisabled, isSeriesEmpty = false, toggleSeries}) => {
  + if (isSeriesEmpty) {
  + return null;
  + }
  const title = `${isDisabled ? 'Show' : 'Hide'} series`;
  return <div className="query-browser__series-btn-wrap">
  @@ -766,6 +770,7 @@ type QueryTableProps = {
  type SeriesButtonProps = {
  colorIndex: number;
  + isSeriesEmpty?: boolean;
  isDisabled: boolean;
  toggleSeries: () => never;
  };
  