patch 8.1.0185: running tests writes lua.vim even though it is not used

Problem:    Running tests writes lua.vim even though it is not used.
Solution:   Stop writing lua.vim.

src/version.c

@@ -789,6 +789,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    185,
 /**/
     184,
 /**/