ui: Allow UI to give feedback to user on account switching
ui: Allow UI to give feedback to user on account switching

Calling `switchAccount` action takes long and the user is not given
any indiction immediately. Use `setTimeout` to allow the UI to first
respond (the button will give feedback) and then call the action.

vishwesh3/zulip-mobile,vishwesh3/zulip-mobile,vishwesh3/zulip-mobile,vishwesh3/zulip-mobile