style(ui): replace dark hover bg from neutral-950 to neutral-900 and use RelativeDate component in UsersPage

src/shared/components/index.js

@@ -28,3 +28,4 @@ export { default as Switch } from './Switch';
 export { default as TagInput } from './TagInput';
 export { default as UserAvatar } from './UserAvatar';
 export { default as ColorPicker } from './ColorPicker.client';
+export { default as RelativeDate } from './RelativeDate.client';