fix(ui5-calendar): re-render header on lang change (#2939)

The CalendarHeader is not language aware, because unlike the Calendar, DatePicker and the rest Date* components, the CalendarHeader is not derived by DateComponentBase class (which is language aware) and thus never re-renders on language change, triggered by the setLanguage API - the week days get translated, but the month text in the CalendarHeader - not.

Author: ilhan007

packages/main/src/CalendarHeader.js

@@ -22,6 +22,7 @@ import styles from "./generated/themes/CalendarHeader.css.js";
 
 const metadata = {
 	tag: "ui5-calendar-header",
+	languageAware: true,
 	properties: {
 		/**
 		 * Already normalized by Calendar