Since the release of Rake 13.0.2, our tests fail, probably because of some load order issue:

+ bundle exec rake pkg:generate_source jenkins:unit TESTOPTS=-v --trace
** Invoke pkg:generate_source (first_time)
** Execute pkg:generate_source
** Invoke jenkins:unit (first_time)
** Invoke jenkins:setup:minitest (first_time)
** Invoke jenkins:setup:pre_ci (first_time)
** Execute jenkins:setup:pre_ci
** Invoke ci:setup:minitest (first_time)
** Execute ci:setup:minitest
rm -rf jenkins/reports/unit/
** Execute jenkins:setup:minitest
** Invoke test:units (first_time)
** Invoke test:prepare (first_time)
** Execute test:prepare
** Execute test:units
pkg/foreman-2.4.0-develop.tar.bz2
The Apipie cache is turned off. Enable it and run apipie:cache rake task to speed up API calls.
The Apipie cache is turned off. Enable it and run apipie:cache rake task to speed up API calls.
WARNING:  SET CONSTRAINTS can only be used in transaction blocks
Mocha deprecation warning at /usr/local/rvm/gems/ruby-2.6.3@test_develop_pr_core-1/gems/activesupport-6.0.3.4/lib/active_support/dependencies.rb:324:in `require': Require 'mocha/test_unit', 'mocha/minitest' or 'mocha/api' instead of 'mocha/setup'.
-- execute("SET CONSTRAINTS ALL DEFERRED;")
   -> 0.0003s
  * DEFERRED: MenuItem::MenuItem#caption should be tested. 
  * DEFERRED: MenuItem::MenuItem#html_options should be tested. 
** Invoke test:functionals (first_time)
** Invoke test:prepare 
** Execute test:functionals
** Invoke test:graphql (first_time)
** Execute test:graphql
/usr/local/rvm/rubies/ruby-2.6.3/bin/ruby -I"lib:test" -r/usr/local/rvm/gems/ruby-2.6.3@test_develop_pr_core-1/gems/rake-13.0.2/lib/rake/rake_test_loader "test/graphql/collection_loader_test.rb" "test/graphql/foreman_graphql_schema_test.rb" "test/graphql/mutations/bookmarks/create_mutation_test.rb" "test/graphql/mutations/bookmarks/delete_mutation_test.rb" "test/graphql/mutations/bookmarks/update_mutation_test.rb" "test/graphql/mutations/hosts/create_mutation_test.rb" "test/graphql/mutations/media/create_mutation_test.rb" "test/graphql/mutations/media/delete_mutation_test.rb" "test/graphql/mutations/media/update_mutation_test.rb" "test/graphql/mutations/models/create_mutation_test.rb" "test/graphql/mutations/models/delete_mutation_test.rb" "test/graphql/mutations/models/update_mutation_test.rb" "test/graphql/mutations/operatingsystems/create_mutation_test.rb" "test/graphql/mutations/operatingsystems/delete_mutation_test.rb" "test/graphql/mutations/operatingsystems/update_mutation_test.rb" "test/graphql/mutations/settings/update_setting_test.rb" "test/graphql/mutations/sign_in_user_mutation_test.rb" "test/graphql/queries/architecture_query_test.rb" "test/graphql/queries/architectures_query_test.rb" "test/graphql/queries/bookmark_query_test.rb" "test/graphql/queries/bookmarks_query_test.rb" "test/graphql/queries/compute_attribute_query_test.rb" "test/graphql/queries/compute_attributes_query_test.rb" "test/graphql/queries/compute_resource_query_test.rb" "test/graphql/queries/compute_resources_query_test.rb" "test/graphql/queries/config_report_query_test.rb" "test/graphql/queries/config_reports_query_test.rb" "test/graphql/queries/current_user_query_test.rb" "test/graphql/queries/domain_query_test.rb" "test/graphql/queries/domains_query_test.rb" "test/graphql/queries/environment_query_test.rb" "test/graphql/queries/environments_query_test.rb" "test/graphql/queries/fact_name_query_test.rb" "test/graphql/queries/fact_names_query_test.rb" "test/graphql/queries/fact_value_query_test.rb" "test/graphql/queries/fact_values_query_test.rb" "test/graphql/queries/host_query_test.rb" "test/graphql/queries/hostgroup_query_test.rb" "test/graphql/queries/hostgroups_query_test.rb" "test/graphql/queries/hosts_query_test.rb" "test/graphql/queries/location_query_test.rb" "test/graphql/queries/locations_query_test.rb" "test/graphql/queries/media_query_test.rb" "test/graphql/queries/medium_query_test.rb" "test/graphql/queries/model_query_test.rb" "test/graphql/queries/models_query_test.rb" "test/graphql/queries/nodes_query_test.rb" "test/graphql/queries/operatingsystem_query_test.rb" "test/graphql/queries/operatingsystems_query_test.rb" "test/graphql/queries/organization_query_test.rb" "test/graphql/queries/organizations_query_test.rb" "test/graphql/queries/personal_access_token_query_test.rb" "test/graphql/queries/personal_access_tokens_query_test.rb" "test/graphql/queries/ptable_query_test.rb" "test/graphql/queries/ptables_query_test.rb" "test/graphql/queries/puppetclass_query_test.rb" "test/graphql/queries/puppetclasses_query_test.rb" "test/graphql/queries/setting_query_test.rb" "test/graphql/queries/settings_query_test.rb" "test/graphql/queries/smart_proxies_query_test.rb" "test/graphql/queries/smart_proxy_query_test.rb" "test/graphql/queries/ssh_key_query_test.rb" "test/graphql/queries/ssh_keys_query_test.rb" "test/graphql/queries/subnet_query_test.rb" "test/graphql/queries/subnets_query_test.rb" "test/graphql/queries/user_query_test.rb" "test/graphql/queries/usergroup_query_test.rb" "test/graphql/queries/usergroups_query_test.rb" "test/graphql/queries/users_query_test.rb" "test/graphql/record_loader_test.rb" "test/graphql/resolvers/collection_test.rb" "test/graphql/resolvers/generic_test.rb" "test/graphql/resolvers/host/power_status_test.rb" -v --ci-reporter
/home/jenkins/workspace/test_develop_pr_core/database/postgresql/ruby/2.6/slave/fast/app/models/application_record.rb:4:in `<class:ApplicationRecord>': uninitialized constant ApplicationRecord::ApipieDSL (NameError)

Pinning Rake to 13.0.1 fixes the issue, I bet it's the changes from https://github.com/ruby/rake/pull/357/files.