Refactor `OC\Server::getTrustedDomainHelper`

Signed-off-by: Andrew Summers <18727110+summersab@users.noreply.github.com>

lib/private/Server.php

@@ -1174,7 +1174,7 @@ class Server extends ServerContainer implements IServerContainer {
 				$classExists = false;
 			}
 
-			if ($classExists && $c->get(\OCP\IConfig::class)->getSystemValueBool('installed', false) && $c->get(IAppManager::class)->isInstalled('theming') && $c->getTrustedDomainHelper()->isTrustedDomain($c->getRequest()->getInsecureServerHost())) {
+			if ($classExists && $c->get(\OCP\IConfig::class)->getSystemValueBool('installed', false) && $c->get(IAppManager::class)->isInstalled('theming') && $c->get(TrustedDomainHelper::class)->isTrustedDomain($c->getRequest()->getInsecureServerHost())) {
 				$imageManager = new ImageManager(
 					$c->get(\OCP\IConfig::class),
 					$c->getAppDataDir('theming'),