Revert "remove unused import"

This reverts commit b9e30b7a529da0d945c40f40822a7719e2798013.

ui/ui-frontend/projects/referential/src/app/context/context-preview/context-information-tab/context-information-tab.component.ts

@@ -45,6 +45,7 @@ import {extend, isEmpty} from 'underscore';
 import {ContextService} from '../../context.service';
 
 import {SecurityProfileService} from '../../../security-profile/security-profile.service';
+import { formatDate } from '@angular/common';
 
 @Component({
   selector: 'app-context-information-tab',