patch 9.1.0985: Vim9: some ex commands can be shortened

Problem:  Vim9: some ex commands can be shortened
Solution: disallow shortening of :abstract, :interface and :type
          (h-east)

closes: #16356

Signed-off-by: h-east <h.east.727@gmail.com>
Signed-off-by: Doug Kearns <dougkearns@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/vim9class.c b/src/vim9class.c
index e85cf82..22db751 100644
--- a/src/vim9class.c
+++ b/src/vim9class.c
@@ -1738,6 +1738,7 @@
 
 /*
  * Handle ":class" and ":abstract class" up to ":endclass".
+ * Handle ":enum" up to ":endenum".
  * Handle ":interface" up to ":endinterface".
  */
     void