Prefer lazy event store initialization

ref: eb73818

Author: lukaszreszke

Diff for: rails_event_store/lib/rails_event_store/async_handler_helpers.rb

@@ -7,14 +7,12 @@ def self.with_defaults
     end
 
     def self.with(
-      event_store: Rails.configuration.event_store,
-      event_store_locator: nil,
-      serializer: RubyEventStore::Serializers::YAML
+      serializer: RubyEventStore::Serializers::YAML,
+      event_store_locator: -> { Rails.configuration.event_store }
     )
       Module.new do
         define_method :perform do |payload|
-          event_store = event_store_locator.call if event_store_locator
-          super(event_store.deserialize(serializer: serializer, **payload.transform_keys(&:to_sym)))
+          super(event_store_locator.call.deserialize(serializer: serializer, **payload.transform_keys(&:to_sym)))
         end
       end
     end

Diff for: rails_event_store/spec/async_handler_helpers_spec.rb

@@ -83,15 +83,14 @@ def perform(_event)
     end
 
     specify "with specified event store" do
-      HandlerWithAnotherEventStore.prepend RailsEventStore::AsyncHandler.with(event_store: another_event_store)
+      HandlerWithAnotherEventStore.prepend RailsEventStore::AsyncHandler.with(event_store_locator: -> { another_event_store} )
       event_store.subscribe_to_all_events(HandlerWithAnotherEventStore)
       event_store.publish(ev = RubyEventStore::Event.new)
       expect($queue.pop).to eq(ev)
     end
 
     specify "with specified event store locator" do
       HandlerWithEventStoreLocator.prepend RailsEventStore::AsyncHandler.with(
-                                             event_store: nil,
                                              event_store_locator: -> { another_event_store }
                                            )
       another_event_store.subscribe_to_all_events(HandlerWithEventStoreLocator)
@@ -101,7 +100,7 @@ def perform(_event)
 
     specify "with specified serializer" do
       HandlerWithSpecifiedSerializer.prepend RailsEventStore::AsyncHandler.with(
-                                               event_store: json_event_store,
+                                               event_store_locator: -> { json_event_store },
                                                serializer: JSON
                                              )
       json_event_store.subscribe_to_all_events(HandlerWithSpecifiedSerializer)