patch 7.4.1458

Problem:    When a JSON channel has a callback it may never be cleared.
Solution:   Do not write "DETACH" into a JS or JSON channel.

src/version.c

@@ -743,6 +743,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1458,
 /**/
     1457,
 /**/