Demo accounts are returned by the API

This is the actual account claimed by JUMBOKILLER2001. It has a skin, too:

• e01c28e44f2443389440e07974a47393

The following are demo accounts (according to MC-51758) all sharing the username "JUMBOKILLER2001", but the response doesn't include anything that indicades they are demo accounts:

• 6d0409ceb40c4580b2075e19d6a12003
• a8e27c733217448ab7166ae32f00799c
• a5d19e7fb70f4a7ab9bfaf02eda2562a
• 311a4cacf4584766aa89212a55d9ea3d

This is a problem because it is not possible to determine which one is the actual account (without additional API calls) and @KrisJelbring said that the intended behavior is to not return demo accounts.