patch 9.0.1746: vim9class compile error for char/char_u conversion

Problem: vim9class compile error for char/char_u conversion
Solution: Correctly cast to (char *)

Signed-off-by: Christian Brabandt <cb@256bit.org>

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1746,
 /**/
     1745,
 /**/