Drop the need for access tokens to have a session

app/models/identity/access_token.rb

@@ -1,14 +1,6 @@
 class Identity::AccessToken < ApplicationRecord
   belongs_to :identity
-  belongs_to :session
 
   has_secure_token
   enum :permission, %w[ read write ].index_by(&:itself), default: :read
-
-  before_validation :build_session, on: :create
-
-  private
-    def build_session
-      self.session = identity.sessions.build(user_agent: "Access Token")
-    end
 end