patch 8.1.0831: xxd test fails if man page has dos fileformat

Problem:    Xxd test fails if man page has dos fileformat.
Solution:   Make a copy with unix fileformat.
diff --git a/src/version.c b/src/version.c
index 9891796..1e5f7e3 100644
--- a/src/version.c
+++ b/src/version.c
@@ -784,6 +784,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    831,
+/**/
     830,
 /**/
     829,