patch 9.1.0697: [security]: heap-buffer-overflow in ins_typebuf

Problem:  heap-buffer-overflow in ins_typebuf
          (SuyueGuo)
Solution: When flushing the typeahead buffer, validate that there
          is enough space left

Github Advisory:
https://github.com/vim/vim/security/advisories/GHSA-4ghr-c62x-cqfh

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

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    697,
 /**/
     696,
 /**/