test(db): retrieve Connection service in DB-req test

Signed-off-by: Josh <josh.t.richards@gmail.com>

Author: joshtrichards

tests/lib/DB/MigrationServiceTest.php

@@ -221,7 +221,7 @@ public function testGetMigration($alias, $expected): void {
 	#[Group('DB')]
 	public function testGetMigratedVersionsSortsByVersionThenDate(): void {
 		/** @var Connection $db */
-		$db = Server::get(IDBConnection::class);
+		$db = Server::get(Connection::class);
 		$appId = 'migration_sort_' . bin2hex(random_bytes(8));
 
 		$migrationService = new class('testing', $db, $appId) extends MigrationService {