patch 8.1.0796: MS-Windows 7: problem with named pipe on channel

Problem:    MS-Windows 7: problem with named pipe on channel.
Solution:   Put back the disconnect/connect calls. (Yasuhiro Matsumoto,
            closes #3833)
diff --git a/src/testdir/test_terminal.vim b/src/testdir/test_terminal.vim
index 960a85e..ea7d4b1 100644
--- a/src/testdir/test_terminal.vim
+++ b/src/testdir/test_terminal.vim
@@ -644,8 +644,7 @@
 
 func Test_terminal_no_cmd()
   " Does not work on Mac.
-  " Todo: make this work on Win32 again
-  if has('mac') || has('win32')
+  if has('mac')
     return
   endif
   let buf = term_start('NONE', {})