patch 7.4.2131

Problem:    More memory leaks when using partial, e.g. for "exit-cb".
Solution:   Don't copy the callback when using a partial.

src/version.c

@@ -763,6 +763,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2131,
 /**/
     2130,
 /**/