remove a boilerplate test that got implemented elsewhere

www/assert/main.js

@@ -516,14 +516,6 @@ define([
         }, "tracker should not timeout");
     }());
 
-    (function () {
-        assert(function (cb) {
-            cb(false);
-
-
-        }, "new format of users' public signing key strings should parse"); // XXX
-    }());
-
     Drive.test(assert);
 
     assert(function (cb) {