patch 8.0.0857: terminal test fails on MS-Windows

Problem:    Terminal test fails on MS-Windows.
Solution:   Sleep a fraction of a second.

src/testdir/test_terminal.vim

@@ -152,6 +152,10 @@ func Test_terminal_scrape()
   call term_wait(1234)
 
   call term_wait(buf)
+  if has('win32')
+    " TODO: this should not be needed
+    sleep 100m
+  endif
   call Check_123(buf)
 
   " Must still work after the job ended.

src/version.c

@@ -769,6 +769,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    857,
 /**/
     856,
 /**/