Remove empty default export

- Removes empty default export from actions and getters

ee/app/assets/javascripts/analytics/productivity_analytics/store/actions.js

 import SET_ENDPOINT from './mutation_types';
+// eslint-disable-next-line import/prefer-default-export
 export const setEndpoint = ({ commit }, endpoint) => commit(SET_ENDPOINT, endpoint);
-
-// prevent babel-plugin-rewire from generating an invalid default during karma tests
-export default () => {};

ee/app/assets/javascripts/analytics/productivity_analytics/store/getters.js

+// eslint-disable-next-line import/prefer-default-export
 export const getMetricTypes = state => chartKey =>
   state.metricTypes.filter(m => m.charts.indexOf(chartKey) !== -1);
-
-// prevent babel-plugin-rewire from generating an invalid default during karma tests
-export default () => {};

ee/app/assets/javascripts/analytics/productivity_analytics/store/modules/charts/actions.js

@@ -90,6 +90,3 @@ export const resetMainChartSelection = ({ commit, dispatch }, skipReload = false
 export const setChartEnabled = ({ commit }, { chartKey, isEnabled }) =>
   commit(types.SET_CHART_ENABLED, { chartKey, isEnabled });
-
-// prevent babel-plugin-rewire from generating an invalid default during karma tests
-export default () => {};

ee/app/assets/javascripts/analytics/productivity_analytics/store/modules/charts/getters.js

@@ -154,6 +154,3 @@ export const hasNoAccessError = state =>
 export const isChartEnabled = state => chartKey => state.charts[chartKey].enabled;
 export const isFilteringByDaysToMerge = state => state.charts[chartKeys.main].selected.length > 0;
-
-// prevent babel-plugin-rewire from generating an invalid default during karma tests
-export default () => {};

ee/app/assets/javascripts/analytics/productivity_analytics/store/modules/filters/actions.js

@@ -61,6 +61,3 @@ export const setDateRange = ({ commit, dispatch }, { skipFetch = false, startDat
     dispatch('table/setPage', 0, { root: true });
   });
 };
-
-// prevent babel-plugin-rewire from generating an invalid default during karma tests
-export default () => {};

ee/app/assets/javascripts/analytics/productivity_analytics/store/modules/filters/getters.js

@@ -19,6 +19,7 @@ import { dateFormats } from '../../../../shared/constants';
  * }
  *
  */
+// eslint-disable-next-line import/prefer-default-export
 export const getCommonFilterParams = state => chartKey => {
   const {
     groupNamespace,
@@ -46,6 +47,3 @@ export const getCommonFilterParams = state => chartKey => {
     merged_at_before: `${dateFormat(endDate, dateFormats.isoDate)}${endOfDayTime}`,
   };
 };
-
-// prevent babel-plugin-rewire from generating an invalid default during karma tests
-export default () => {};