Fix: failing tests when running on none english os. (#22913)

public/app/core/utils/richHistory.ts

@@ -2,7 +2,7 @@
 import _ from 'lodash';
 
 // Services & Utils
-import { DataQuery, ExploreMode } from '@grafana/data';
+import { DataQuery, ExploreMode, dateTime } from '@grafana/data';
 import { renderUrl } from 'app/core/utils/url';
 import store from 'app/core/store';
 import { serializeStateToUrlParam, SortOrder } from './explore';
@@ -212,10 +212,7 @@ export const createRetentionPeriodBoundary = (days: number, isLastTs: boolean) =
 };
 
 export function createDateStringFromTs(ts: number) {
-  const date = new Date(ts);
-  const month = date.toLocaleString('default', { month: 'long' });
-  const day = date.getDate();
-  return `${month} ${day}`;
+  return dateTime(ts).format('MMMM D');
 }
 
 export function getQueryDisplayText(query: DataQuery): string {