devise-jwt: Error with JWTBlackList in rails 6

Hi,

Following the readme file to create a JWTBlackList results into an error.

uninitialized constant User (call 'User.connection' to establish a connection)::JWTBlacklist (NameError) Did you mean?  JwtBlacklist

Expected behavior

No error.

Actual behavior

Throws error

`<class:User>': uninitialized constant User (call 'User.connection' to establish a connection)::JWTBlacklist (NameError) Did you mean?  JwtBlacklist

Steps to Reproduce the Problem

1. Create a new rails app
2. Install Devise
3. Install Devise-jwt
4. Create JWTBlacklist model (jwt_blacklist.rb) and migration
5. Add the following to User model (user.rb)

  devise :database_authenticatable,
         :jwt_authenticatable, jwt_revocation_strategy: JWTBlacklist

Debugging information

devise-jwt versions 0.5.9 and 0.6.0 rails version 6.0.0

Solutions

Downgrade to 5.2

Downgrading config.load_defaults 6.0 to 5.2.

Rename filename of JwtBlacklist model

renaming filename of JwtBlacklist model fromjwt_blacklist.rb to j_w_t_blacklist.rb.

Rename JwtBlacklist model

Renaming model from JwtBlacklist to JwtBlacklist