patch 8.2.4722: ending recording with mapping records too much

Problem:    When a recording is ended with a mapped key that key is also
            recorded.
Solution:   Remember the previous last_recorded_len. (closes #10122)

src/version.c

@@ -746,6 +746,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    4722,
 /**/
     4721,
 /**/