Standardize aggregator entity route names

1. +++ b/core/modules/aggregator/src/Controller/AggregatorController.php
   @@ -229,7 +229,7 @@ public function sources() {
   -      $feed->url = $this->url('aggregator.feed_view', array('aggregator_feed' => $feed->id()));
   +      $feed->url = $this->url('entity.aggregator_feed.canonical', array('aggregator_feed' => $feed->id()));
   

   OT: But why do we actually need this ... can't we use $feed->uriInfo() directly somehow?

2. +++ b/core/modules/aggregator/tests/src/Menu/AggregatorLocalTasksTest.php
   @@ -49,7 +49,7 @@ public function getAggregatorAdminRoutes() {
   +      0 => array('entity.aggregator_feed.canonical', 'entity.aggregator_feed.edit_form'),
   

   The big advantage is that it is easier to actually get the right route name. This is quite a DX win tbh.

Committed and pushed to 8.x. Thanks!