patch 8.2.4445: exit test fails on MS-Windows anyway

Problem:    Exit test fails on MS-Windows anyway.
Solution:   Skip the test on MS-Windows.
diff --git a/src/testdir/test_exit.vim b/src/testdir/test_exit.vim
index a5cabf8..7e50e78 100644
--- a/src/testdir/test_exit.vim
+++ b/src/testdir/test_exit.vim
@@ -112,6 +112,7 @@
 
 func Test_exit_error_reading_input()
   CheckNotGui
+  CheckNotMSWindows
   " The early exit causes memory not to be freed somehow
   CheckNotAsan