Deprecation warnings for Rails 6.0

DEPRECATION: DEPRECATION WARNING: Dangerous query method (method whose arguments are used as raw SQL) called with non-attribute argument(s): "DISTINCT users.id". Non-attribute arguments will be disallowed in Rails 6.0. This method should not be called with user-provided values, such as request parameters or model attributes. Known-safe values can be passed by wrapping them in Arel.sql(). 

called from get_peer_ids at /home/dora/Dev/crabgrass_project/crabgrass/app/models/user/cache.rb:202
called from most_active at /home/dora/Dev/crabgrass_project/crabgrass/app/models/user/users.rb:58
called from body_terms at /home/dora/Dev/crabgrass_project/crabgrass/extensions/pages/task_list_page/app/models/task_list_page.rb:13