Contact email of existent sudt should be updated to ckb-explorer@magickbase.com

[Keith-CY]

The feature of submit token info through API(#374) is going to be online and a field contact email is required when users try to update info of an existent token.

But those submitted by e-mail don't have a contact email, which blocks them being updated on the page.

Here I suggest setting all existent sudts with a contact email ckb-explorer@magickbsae.com, the one that belongs to the project maintainer.

By doing so, the information can be updated by the maintainer without updating database directly.

[zmcNotafraid]

Finished.