fix: prevent clearing of language selection on account view (#6803)

Fixes https://github.com/payloadcms/payload/issues/6794

Users should not be able to clear their language selection on the
account view.

packages/next/src/views/Account/Settings/LanguageSelector.tsx

@@ -17,6 +17,7 @@ export const LanguageSelector: React.FC<{
   return (
     <ReactSelect
       inputId="language-select"
+      isClearable={false}
       onChange={async (option: Option<AcceptedLanguages>) => {
         await switchLanguage(option.value)
       }}