git-gui: Fix the Remote menu separator.
git-gui: Fix the Remote menu separator.

It was positioned incorrectly (offset by one position)
if the menu had a tear-off handle.

Signed-off-by: Alexander Gavrilov <75c96f70141fec65a655d202cd4821a09cb99fd1@gmail.com>
Signed-off-by: Shawn O. Pearce <f01032651c12a22b2103346ba96b3b6b231f9d3c@spearce.org>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git