After some discussion with @ashoat and @atul about how to fetch the ens avatars we decided to have two separate components to render avatars: `UserAvatar` and `ThreadAvatar`. This diff handles `ThreadAvatar`.
Generally, a thread avatar should not be able an ENS avatar since we won't be able to set it; however, if the thread type is either `PRIVATE` or `PERSONAL` then if the user avatar type is `ens` then we need to render the ens user avatar