fetch: convert argv_gc_auto to struct argv_array

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/fetch.c

@@ -1110,9 +1110,7 @@ int cmd_fetch(int argc, const char **argv, const char *prefix)
 	struct string_list list = STRING_LIST_INIT_NODUP;
 	struct remote *remote;
 	int result = 0;
-	static const char *argv_gc_auto[] = {
-		"gc", "--auto", NULL,
-	};
+	struct argv_array argv_gc_auto = ARGV_ARRAY_INIT;
 
 	packet_trace_identity("fetch");
 
@@ -1198,7 +1196,9 @@ int cmd_fetch(int argc, const char **argv, const char *prefix)
 	list.strdup_strings = 1;
 	string_list_clear(&list, 0);
 
-	run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
+	argv_array_pushl(&argv_gc_auto, "gc", "--auto", NULL);
+	run_command_v_opt(argv_gc_auto.argv, RUN_GIT_CMD);
+	argv_array_clear(&argv_gc_auto);
 
 	return result;
 }