A0CLI-47: add initial role support.

[rene00]

Description

This PR adds initial Role support to auth0-cli.

List all roles:

$ auth0 roles list

Create a new role:

$ auth0 roles create --name myRoleName --description myRoleDescription

Get an existing role:

$ auth0 roles get --role-id myRoleID

Update a role:

$ auth0 roles update --role-id myRoleID --name myNewRoleName --description myNewRoleDescription

Delete a role:

$ auth0 roles delete --role-id myRoleID

Demo in slack thread.

References

• A0CLI-47
• https://auth0.slack.com/archives/C01KGNSRS4C/p1611704673330400

Testing

• This change adds test coverage for new/changed/fixed functionality

Checklist

• I have added documentation for new/changed functionality in this PR or in auth0.com/docs
• All active GitHub checks for tests, formatting, and security are passing
• The correct base branch is being used, if not master

[cyx]

Nice!