Return primary key expiry based on userId param in getExpirationTime

src/key.js

@@ -501,7 +501,7 @@ Key.prototype.verifyPrimaryKey = async function(date=new Date(), userId={}) {
  * @async
  */
 Key.prototype.getExpirationTime = async function(capabilities, keyId, userId) {
-  const primaryUser = await this.getPrimaryUser(null);
+  const primaryUser = await this.getPrimaryUser(null, userId);
   if (!primaryUser) {
     throw new Error('Could not find primary user');
   }