Update activity registry & workflow definitions

This commit removes unnecessary calls related to populating activity registry and reinitializing workflow definitions.

src/modules/Elsa.Workflows.Management/Contracts/IActivityRegistryPopulator.cs

@@ -12,13 +12,6 @@ public interface IActivityRegistryPopulator
     /// </summary>
     /// <param name="cancellationToken">The cancellation token.</param>
     Task PopulateRegistryAsync(CancellationToken cancellationToken = default);
-    
-    /// <summary>
-    /// Populates the <see cref="IActivityRegistry"/> with activities for the specified provider.
-    /// </summary>
-    /// <param name="providerType">The type of the provider.</param>
-    /// <param name="cancellationToken">The cancellation token.</param>
-    Task PopulateRegistryAsync(Type providerType, CancellationToken cancellationToken = default);
 
     /// <summary>
     /// Tries to add a workflow as an activity to the registry.

src/modules/Elsa.Workflows.Management/Services/WorkflowDefinitionPublisher.cs

@@ -148,7 +148,6 @@ public class WorkflowDefinitionPublisher : IWorkflowDefinitionPublisher
             throw new InvalidOperationException("Cannot retract an unpublished workflow definition.");
 
         definition.IsPublished = false;
-        definition = Initialize(definition);
 
         await _notificationSender.SendAsync(new WorkflowDefinitionRetracting(definition), cancellationToken);
         await _workflowDefinitionStore.SaveAsync(definition, cancellationToken);

src/modules/Elsa.Workflows.Runtime/Services/DefaultRegistriesPopulator.cs

@@ -25,7 +25,7 @@ public class DefaultRegistriesPopulator : IRegistriesPopulator
         // Stage 1: Populate the activity registry.
         // Because workflow definitions can be used as activities, we need to make sure that the activity registry is populated before we populate the workflow definition store.
         await _activityRegistryPopulator.PopulateRegistryAsync(cancellationToken);
-
+        
         // Stage 2: Populate the workflow definition store.
         await _workflowDefinitionStorePopulator.PopulateStoreAsync(false, cancellationToken);