patch 8.2.0720: occasional exit when encountering an X error

Problem:    Occasional exit when encountering an X error. (Manfred Lotz)
Solution:   On an X error do not exit, do preserve files.

src/version.c

@@ -746,6 +746,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    720,
 /**/
     719,
 /**/