patch 8.0.0256: missing changes to one file breaks test

Problem:    Tests fail because some changes were not included.
Solution:   Add changes to evalfunc.c
diff --git a/src/version.c b/src/version.c
index 4d73ae6..58c9d29 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    256,
+/**/
     255,
 /**/
     254,