Refactor: change constant var to class method in query limiting

...atures/boards/swimlanes/epics_swimlanes_filtering_spec.rb

ee/spec/features/issues/user_bulk_edits_issues_spec.rb

...rge_trains/user_adds_merge_request_to_merge_train_spec.rb

ee/spec/features/registrations/combined_registration_spec.rb

...pec/features/registrations/saas_user_registration_spec.rb

ee/spec/requests/api/epics_spec.rb

...ests/api/graphql/mutations/issues/promote_to_epic_spec.rb

...ns/security_policy/create_security_policy_project_spec.rb

ee/spec/requests/projects/merge_requests_controller_spec.rb

ee/spec/requests/registrations/project_creation_spec.rb

lib/gitlab/query_limiting/transaction.rb

...atures/projects/settings/user_transfers_a_project_spec.rb

spec/lib/gitlab/query_limiting/transaction_spec.rb

spec/requests/api/internal/base_spec.rb

spec/support/helpers/graphql_helpers.rb

..._examples/requests/api/issuable_update_shared_examples.rb