Fix wrong timeout and mock method in radio VTS

Fixed wrong time unit convension for timeout values used in broadcast
radio HAL VTS. Also replaced tuner callback mock method which caused
segmentation fault when unimplemented callback methods are called. In
addition, antenna connection state was checked at the end of the each
test instead of at the beginning.

Bug: 277531858
Test: atest VtsHalBroadcastradioAidlTargetTest
Change-Id: Ied70fcfd2742ae5d253aec984e2161afa6f65162