patch 8.2.3408: can delete a numbered function

Problem:    Can delete a numbered function. (Naohiro Ono)
Solution:   Disallow deleting a numbered function. (closes #8760)
diff --git a/src/version.c b/src/version.c
index 6301d77..54533dc 100644
--- a/src/version.c
+++ b/src/version.c
@@ -756,6 +756,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3408,
+/**/
     3407,
 /**/
     3406,