[Android] When viewing a server you have not boosted, While already having a boost, Display a message to say you need to stop boosting first

On the new Boosting feature in 9.1.3, If you view a server that you are not boosted on, while boosting another server it will still show a button to "Boost this server", instead replace this with a "You need to cancel your existing boost, before you can boost this server" or something!