patch 8.0.0604: gF test fails still on MS-Windows

Problem:    gF test fails still on MS-Windows.
Solution:   Use : before the line number and remove it from 'isfname'.

src/version.c

@@ -764,6 +764,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    604,
 /**/
     603,
 /**/