git:checkout-worktree: Pass all arguments

Pass all given arguments to `git worktree add`. This makes it possible
to directly create a new branch with `-b` for example. As the arguments
are not used anywhere else, this should not introduce any parsing
issues.

.config/zsh/autoload/git/git-checkout-worktree

@@ -36,7 +36,7 @@ trap '
 	return $errc
 ' INT QUIT TERM EXIT
 
-git worktree add "$WORKTREE_PATH" "$1"
+git worktree add "$WORKTREE_PATH" "$@"
 pushd -q "$WORKTREE_PATH"
 
 "$SHELL" && errc=$? || errc=$?