Eliminate usage of OpenStruct

OpenStruct design cause it to have non-local performance impact,
especially with JIT compilers.

See ruby/ostruct#51 for full context,
and it Ruby 3.3 OpenStruct usage raise a performance warnings:

```
gems/state_machines-audit_trail-2.0.2/lib/state_machines/audit_trail/transition_auditing.rb:38:
warning: OpenStruct use is discouraged for performance reasons
```

In this case I don't really see any advantage of OpenStruct
over a simple PORO.

lib/state_machines/audit_trail/transition_auditing.rb

@@ -1,4 +1,3 @@
-require 'ostruct'
 #
 # This module inserts hooks into the state machine.
 # The transition_class is the class (optionally specified with the :class option) for the model which
@@ -7,6 +6,14 @@
 # Multiple `SubscriptionStateTransition`s compose the 'audit_trail'.
 #
 module StateMachines::AuditTrail::TransitionAuditing
+  class LogInfo
+    attr_reader :namespace, :to
+
+    def initialize(namespace:, to:)
+      @namespace = namespace
+      @to = to
+    end
+  end
 
   # Hook for audit_trail inside a a state_machine declaration.
   #
@@ -35,7 +42,7 @@ def audit_trail(options = {})
           if state_machine.backend.new_record? object
             current_state = object.send(state_machine.attribute)
             if !current_state.nil?
-              state_machine.backend.log(object, OpenStruct.new(namespace: state_machine.namespace, to: current_state))
+              state_machine.backend.log(object, LogInfo.new(namespace: state_machine.namespace, to: current_state))
             end
           end
         end