fix: put translation keys in wrong file

Author: mikerodonnell89

libs/i18n/src/lib/models/fd-language.ts

@@ -187,6 +187,9 @@ export interface FdLanguage {
         collapsedItemMenuLabel: FdLanguageKey;
         cancel: FdLanguageKey;
         search: FdLanguageKey;
+        assistiveTools: FdLanguageKey;
+        backButtonLabel: FdLanguageKey;
+        navigationButtonLabel: FdLanguageKey;
     };
     coreSlider: {
         /**