dns: fqdn only needs domain string

This is from the caas days, when we had hyphenated subdomains flag

src/dns/linode.js

@@ -225,7 +225,7 @@ async function wait(domainObject, subdomain, type, value, options) {
     assert.strictEqual(typeof value, 'string');
     assert(options && typeof options === 'object'); // { interval: 5000, times: 50000 }
 
-    const fqdn = dns.fqdn(subdomain, domainObject);
+    const fqdn = dns.fqdn(subdomain, domainObject.domain);
 
     await waitForDns(fqdn, domainObject.zoneName, type, value, options);
 }