patch 8.2.0222: Vim9: optional function arguments don't work yet

Problem:    Vim9: optional function arguments don't work yet.
Solution:   Implement optional function arguments.
diff --git a/src/version.c b/src/version.c
index f302040..09f9e9c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -743,6 +743,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    222,
+/**/
     221,
 /**/
     220,