Bump JWT core to 1.87.0 for Cognito Token support.

[Duslerke]

What:

• Update the Hackney.Core.JWT package multiple versions up (1.49 -> ... -> 1.87).

Why:

• To get the latest version of the ITokenFactory implementation that adds support for the Cognito token schema.

Notes:

• The versions in between have no consequence as the only thing the JWT package is used here for is to inject TokenFactory so that logger could use it to extract user email. The Token schema for email hasn't changed. In fact, the only thing that changed about Token schema is Nbf, Exp, and Iat field types being changed from int to long.
• What changes does latest (v1.87.0) JWT intoduce? See PR: Add cognito authentication flow token schema support. lbh-core#68.