Revert "Development workaround for Concurrent-Ruby x MRI x Mutant issues."
Revert "Development workaround for Concurrent-Ruby x MRI x Mutant issues."

This reverts commit 7477ca3967adc6460346ee307c7382da59a11cc9.

arkency/rails_event_store,mpraglowski/rails_event_store,RailsEventStore/rails_event_store,arkency/rails_event_store,arkency/rails_event_store,mpraglowski/rails_event_store,arkency/rails_event_store,RailsEventStore/rails_event_store,mpraglowski/rails_event_store,mpraglowski/rails_event_store,RailsEventStore/rails_event_store,RailsEventStore/rails_event_store