Using CSTRZ mapping type for go executable.

src/nxt_main_process.c

@@ -148,7 +148,7 @@ static nxt_conf_map_t  nxt_common_app_conf[] = {
 
     {
         nxt_string("executable"),
-        NXT_CONF_MAP_STR,
+        NXT_CONF_MAP_CSTRZ,
         offsetof(nxt_common_app_conf_t, u.go.executable),
     },
 };