test: add tests for message unqueueing

This adds a comprehensive set of tests for the message unqueueing service.

Additionally, it improves how message databases are used for testing environments.

spec/rails_helper.rb

@@ -14,8 +14,10 @@ DatabaseCleaner.allow_remote_database_url = true
 ActiveRecord::Base.logger = Logger.new("/dev/null")
 
 Dir[File.expand_path("factories/*.rb", __dir__)].each { |f| require f }
+Dir[File.expand_path("helpers/**/*.rb", __dir__)].each { |f| require f }
 
 ActiveRecord::Migration.maintain_test_schema!
+
 RSpec.configure do |config|
   config.use_transactional_fixtures = true
   config.infer_spec_type_from_file_location!
@@ -25,29 +27,9 @@ RSpec.configure do |config|
   config.before(:suite) do
     # Test that the factories are working as they should and then clean up before getting started on
     # the rest of the suite.
-    begin
-      DatabaseCleaner.start
-      FactoryBot.lint
-    ensure
-      DatabaseCleaner.clean
-    end
-
-    # We're going to create a global server that can be used by any tests.
-    # Because the mail databases don't use any transactions, all data left in the
-    # database will be left there unless removed.
     DatabaseCleaner.start
-
-    # rubocop:disable Lint/ConstantDefinitionInBlock
-    GLOBAL_SERVER = FactoryBot.create(:server, provision_database: true)
-    # rubocop:enable Lint/ConstantDefinitionInBlock
-  end
-
-  config.after(:suite) do
-    # Remove the global server after the suite has finished running and then
-    # clean the database in case it left anything lying around.
-    if defined?(GLOBAL_SERVER)
-      GLOBAL_SERVER.destroy
-      DatabaseCleaner.clean
-    end
+    FactoryBot.lint
+  ensure
+    DatabaseCleaner.clean
   end
 end