patch 8.1.0807: session test fails on MS-Windows

Problem:    Session test fails on MS-Windows.
Solution:   Don't try creating file with illegal name.

src/testdir/test_mksession.vim

@@ -427,6 +427,10 @@ func Test_mksession_no_errmsg()
 endfunc
 
 func Test_mksession_quote_in_filename()
+  if !has('unix')
+    " only Unix can handle this weird filename
+    return
+  endif
   let v:errmsg = ''
   %bwipe!
   split another

src/version.c

@@ -791,6 +791,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    807,
 /**/
     806,
 /**/