patch 8.2.1268: Vim9: no error for using double quote comment

Problem:    Vim9: no error for using double quote comment after :func or :def.
Solution:   Only accept double quote when not in Vim9 script and not after
            :def. (closes #6483)

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1268,
 /**/
     1267,
 /**/