Updated code according to latest standards (where possible)

Closes #3449070

src/Cache/Context/DomainGroupCacheContext.php

@@ -6,7 +6,7 @@ use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Cache\Context\CacheContextInterface;
 use Drupal\Core\Entity\EntityRepositoryInterface;
 use Drupal\domain\DomainNegotiatorInterface;
-use Drupal\group_context_domain\Context\GroupFromDomainContextTrait;
+use Drupal\group_context_domain\GroupFromDomainContextTrait;
 
 /**
  * Defines a cache context for "per group from domain" caching.
@@ -17,17 +17,10 @@ class DomainGroupCacheContext implements CacheContextInterface {
 
   use GroupFromDomainContextTrait;
 
-  /**
-   * Constructs a new DomainGroupCacheContext.
-   *
-   * @param \Drupal\domain\DomainNegotiatorInterface $domain_negotiator
-   *   The domain negotiator.
-   * @param \Drupal\Core\Entity\EntityRepositoryInterface $entity_repository
-   *   The entity repository.
-   */
-  public function __construct(DomainNegotiatorInterface $domain_negotiator, EntityRepositoryInterface $entity_repository) {
-    $this->domainNegotiator = $domain_negotiator;
-    $this->entityRepository = $entity_repository;
+  public function __construct(
+    protected DomainNegotiatorInterface $domainNegotiator,
+    protected EntityRepositoryInterface $entityRepository,
+  ) {
   }
 
   /**