🐛(frontend) fix React aria warnings with label/wrapper investigation

Attempt to resolve React aria warnings by adding aria-label to form
components. Visual label should be reusable by screen readers, but
warning persists with only form wrapper as apparent difference.

Uncertain if warning is harmful. Added aria-label as potential fix but
removed after feedback from Sophie and Manu. Warning remains annoying
during development.

src/frontend/src/features/rooms/components/Join.tsx

@@ -325,6 +325,7 @@ export const Join = ({
                 type="text"
                 onChange={saveUsername}
                 label={t('usernameLabel')}
+                aria-label={t('usernameLabel')}
                 defaultValue={username}
                 validate={(value) => !value && t('errors.usernameEmpty')}
                 wrapperProps={{