Add member role to TeamMailboxRepository API

[quantranhong1999]

Why

TeamMailboxRepository needs to be acknowledged about member role (manager / member) now.

How

• Introduce a TeamMailboxMember POJO = Username + MemberRole (could be an enum)

• Refactor the TeamMailboxRepository API to use TeamMailboxMember instead of Username:

  def addMember(teamMailbox: TeamMailbox, addUser: TeamMailboxMember): Publisher[Void]
  
  def removeMember(teamMailbox: TeamMailbox, removeUser: TeamMailboxMember): Publisher[Void]
  
  def listMembers(teamMailbox: TeamMailbox): Publisher[TeamMailboxMember]

  If manager role, we add the a right for that user. Otherwise we keep it the same as today.

  Upon getting a member, we can use RightManager.hasRightReactive to see if the user is a manager.

• Adapt the contract tests to cover the cases.

DoD

Pass contract tests.

[quantranhong1999]

https://github.com/linagora/tmail-backend/pull/1098