build: upgrade to angular v12

src/app/translation/common-string-pipes.ts

@@ -18,7 +18,8 @@ import {LangChangeEvent, TranslateService} from '@ngx-translate/core';
 import moment from 'moment';
 import {Subscription} from 'rxjs';
 import {logger} from '../_helpers/ts-logger';
-
+// TODO: use import for opening_hours when the change is published with a new update
+// see https://github.com/opening-hours/opening_hours.js/pull/407
 // eslint-disable-next-line @typescript-eslint/no-var-requires, unicorn/prefer-module
 const ohFunction = require('opening_hours');