gc: remove unused launchctl_get_uid() call

When the launchctl_boot_plist() function was added in
a16eb6b1ff (maintenance: skip bootout/bootstrap when plist is
registered, 2021-08-24), an unused call to launchctl_get_uid() was
added along with it. That call appears to have been copy/pasted from
launchctl_boot_plist().

Since we can remove that, we can also get rid of the "result"
variable, whose only purpose was allow for the free() between its
assignment and the return. That pattern also appears to have been
copy/pasted from launchctl_boot_plist().

As the patch shows the returned value from launchctl_get_uid() wasn't
used at all in this function. The launchctl_get_uid() function itself
just calls xstrfmt() and getuid(), neither of which have any subtle
global side-effects, so this removal is safe.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/gc.c

@@ -1602,9 +1602,7 @@ static int launchctl_remove_plists(const char *cmd)
 
 static int launchctl_list_contains_plist(const char *name, const char *cmd)
 {
-	int result;
 	struct child_process child = CHILD_PROCESS_INIT;
-	char *uid = launchctl_get_uid();
 
 	strvec_split(&child.args, cmd);
 	strvec_pushl(&child.args, "list", name, NULL);
@@ -1615,12 +1613,8 @@ static int launchctl_list_contains_plist(const char *name, const char *cmd)
 	if (start_command(&child))
 		die(_("failed to start launchctl"));
 
-	result = finish_command(&child);
-
-	free(uid);
-
 	/* Returns failure if 'name' doesn't exist. */
-	return !result;
+	return !finish_command(&child);
 }
 
 static int launchctl_schedule_plist(const char *exec_path, enum schedule_priority schedule, const char *cmd)