Autofix Rubocop RSpec/BeNil (#23653)

.rubocop_todo.yml

spec/controllers/accounts_controller_spec.rb

spec/controllers/activitypub/collections_controller_spec.rb

spec/controllers/activitypub/outboxes_controller_spec.rb

spec/controllers/activitypub/replies_controller_spec.rb

spec/controllers/api/v1/apps_controller_spec.rb

spec/controllers/api/v1/statuses_controller_spec.rb

spec/controllers/instance_actors_controller_spec.rb

spec/controllers/statuses_controller_spec.rb

spec/models/account_statuses_cleanup_policy_spec.rb

spec/models/concerns/account_interactions_spec.rb

spec/models/session_activation_spec.rb

spec/models/user_spec.rb