core: fix url generation with domainId

packages/hydrooj/src/service/layers/renderer.ts

@@ -52,7 +52,7 @@ export default (router, logger) => async (ctx: KoaContext, next) => {
                 || (host instanceof Array
                     ? (!host.includes(request.host))
                     : request.host !== host)
-            )) withDomainId = domainId;
+            )) withDomainId ||= domainId;
             res = router.url(name, args, { query }).toString();
             if (anchor) res = `${res}#${anchor}`;
             if (withDomainId) res = `/d/${withDomainId}${res}`;