fix(frontend): fixed changing location

before we were setting the location on the window when we should have been just using Angular $location service instead

[TESTING -> tested locally with docker compose and a complete build]

- [ ] It works!
- [ ] Comments provide sufficient explanations for the next contributor
- [ ] Tests cover changes and corner cases
- [ ] Follows Quay syntax patterns and format

static/js/directives/ui/signup-form.js

@@ -38,7 +38,8 @@ angular.module('quay').directive('signupForm', function () {
           $scope.userRegistered({'username': $scope.newUser.username});
 
           if (!$scope.awaitingConfirmation && !$scope.inviteCode) {
-            document.location = '/';
+            $location.path("/");
+
           }
 
           UserService.load();