trySendMessages: Simplify with an early `return`
trySendMessages: Simplify with an early `return`

Pure refactor. Simplifies `trySendMessages` by unwrapping the whole
body out of the `if` and does an early `return` instead.

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