patch 8.2.2223: Vim9: Reloading marks a :def function as deleted

Problem:    Vim9: Reloading marks a :def function as deleted.
Solution:   Clear the function contents but keep the index.
diff --git a/src/version.c b/src/version.c
index f488d77..00e5596 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2223,
+/**/
     2222,
 /**/
     2221,