patch 8.2.1660: assert functions require passing expected as first argument

Problem:    Assert functions require passing expected result as the first
            argument, which isn't obvious.
Solution:   Use a method, as in "runtest()->assert_equal(expected)".

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1660,
 /**/
     1659,
 /**/