patch 8.2.0477: Vim9: error messages not tested

Problem:    Vim9: error messages not tested.
Solution:   Add more tests.
diff --git a/src/version.c b/src/version.c
index 73de61c..13a1c30 100644
--- a/src/version.c
+++ b/src/version.c
@@ -739,6 +739,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    477,
+/**/
     476,
 /**/
     475,