Fix alert banner entity type paths and local tasks

Fix #342

Use the standard drupal paths (entity_type/manage) for the alert banner
entity type routes, and add a local task for the edit link.
This restores expected behaviour with edit, fields, manage form,
manage display,  permissions.

Remove unneed entity type route provider and remove todo comment
from entity type list builder.

localgov_alert_banner.links.task.yml

@@ -28,3 +28,8 @@ entity.localgov_alert_banner.collection:
   base_route: system.admin_content
   title: 'Alert banners'
   weight: 30
+
+entity.localgov_alert_banner_type.edit_form:
+  title: Edit
+  route_name: entity.localgov_alert_banner_type.edit_form
+  base_route: entity.localgov_alert_banner_type.edit_form

src/AlertBannerEntityTypeListBuilder.php

@@ -25,7 +25,6 @@ public function buildHeader() {
   public function buildRow(EntityInterface $entity) {
     $row['label'] = $entity->label();
     $row['id'] = $entity->id();
-    // You probably want a few more properties here...
     return $row + parent::buildRow($entity);
   }
 

src/Entity/AlertBannerEntityType.php

@@ -25,7 +25,7 @@
  *       "delete" = "Drupal\localgov_alert_banner\Form\AlertBannerEntityTypeDeleteForm"
  *     },
  *     "route_provider" = {
- *       "html" = "Drupal\localgov_alert_banner\AlertBannerEntityTypeHtmlRouteProvider",
+ *       "html" = "Drupal\Core\Entity\Routing\AdminHtmlRouteProvider",
  *       "permissions" = "Drupal\user\Entity\EntityPermissionsRouteProvider",
  *     },
  *   },
@@ -42,12 +42,11 @@
  *     "label"
  *   },
  *   links = {
- *     "canonical" = "/admin/structure/alert-banner-types/{localgov_alert_banner_type}",
- *     "add-form" = "/admin/structure/alert-banner-types/add",
- *     "edit-form" = "/admin/structure/alert-banner-types/{localgov_alert_banner_type}/edit",
- *     "delete-form" = "/admin/structure/alert-banner-types/{localgov_alert_banner_type}/delete",
- *     "entity-permissions-form" = "/admin/structure/alert-banner-types/{localgov_alert_banner_type}/permissions",
- *     "collection" = "/admin/structure/alert-banner-types"
+ *     "add-form" = "/admin/structure/localgov_alert_banner_types/add",
+ *     "edit-form" = "/admin/structure/localgov_alert_banner_types/manage/{localgov_alert_banner_type}",
+ *     "delete-form" = "/admin/structure/localgov_alert_banner_types/manage/{localgov_alert_banner_type}/delete",
+ *     "entity-permissions-form" = "/admin/structure/localgov_alert_banner_types/manage/{localgov_alert_banner_type}/permissions",
+ *     "collection" = "/admin/structure/localgov_alert_banner_types"
  *   }
  * )
  */