patch 8.2.4413: Vim9: Coverity warns for using NULL pointer

Problem:    Vim9: Coverity warns for using NULL pointer.
Solution:   Give an internal error when funcref function can't be found.
diff --git a/src/version.c b/src/version.c
index 9db5ad3..cbe988b 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4413,
+/**/
     4412,
 /**/
     4411,