chore: support set roles for user in workspace level & support group

[ecmadao]

• Support set roles for user in workspace level

resource "bytebase_user" "workspace_dba" {
  title = "DBA"
  email = "[email protected]"

  # Grant workspace level roles.
  roles = ["roles/workspaceDBA", "roles/projectViewer"]
}

• Support group

resource "bytebase_group" "developers" {
  depends_on = [
    bytebase_user.workspace_dba,
    bytebase_user.project_developer
  ]

  email = "[email protected]"
  title = "Bytebase Developers"

  members {
    member = format("users/%s", bytebase_user.workspace_dba.email)
    role   = "OWNER"
  }

  members {
    member = format("users/%s", bytebase_user.project_developer.email)
    role   = "MEMBER"
  }
}