patch 8.0.0185: system() test fails on MS-Windows

Problem:    The system() test fails on MS-Windows.
Solution:   Skip the test on MS-Windows.
diff --git a/src/version.c b/src/version.c
index be361f5..d5fa549 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    185,
+/**/
     184,
 /**/
     183,