[WIP] Fix error when trying to view a workflow instance

[Copilot]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Error when trying to view a workflow instance</issue_title>
<issue_description>## Description
I have been getting this issue across multiple versions of Elsa and for certain workflow definitions, although pretty inconsistent as to why as they don't use the same activities.

I get an error when trying to view the instance, in production the error is NullReferenceException: Arg_NullReferenceException

when running locally it is NullReferenceException: Object reference not set to an instance of an object.

4. Reproduction Rate: every time

Expected Behavior

View the instance

Actual Behavior

Error is thrown

Screenshots

Environment

• Elsa Package Version: 3.4.0

Log Output

  Sending HTTP request POST https://localhost:44397/elsa/api/workflow-instances/83def16940ce37f8/journal?*

info: System.Net.Http.HttpClient.IWorkflowInstancesApi.ClientHandler[101]
Received HTTP response headers after 50.6ms - 200
info: System.Net.Http.HttpClient.IWorkflowInstancesApi.LogicalHandler[101]
End processing HTTP request after 63.1ms - 200
fail: Microsoft.AspNetCore.Components.Web.ErrorBoundary[0]
System.NullReferenceException: Object reference not set to an instance of an object.
at Elsa.Studio.Workflows.Components.WorkflowInstanceViewer.Components.WorkflowInstanceDetails.GetLastWorkflowActivityExecutionRecordAsync(String workflowInstanceId)
at Elsa.Studio.Workflows.Components.WorkflowInstanceViewer.Components.WorkflowInstanceDetails.GetWorkflowActivityExecutionRecordAsync(String workflowInstanceId)
at Elsa.Studio.Workflows.Components.WorkflowInstanceViewer.Components.WorkflowInstanceDetails.OnParametersSetAsync()
at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
System.NullReferenceException: Object reference not set to an instance of an object.
at Elsa.Studio.Workflows.Components.WorkflowInstanceViewer.Components.WorkflowInstanceDetails.GetLastWorkflowActivityExecutionRecordAsync(String workflowInstanceId)
at Elsa.Studio.Workflows.Components.WorkflowInstanceViewer.Components.WorkflowInstanceDetails.GetWorkflowActivityExecutionRecordAsync(String workflowInstanceId)
at Elsa.Studio.Workflows.Components.WorkflowInstanceViewer.Components.WorkflowInstanceDetails.OnParametersSetAsync()
at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)</issue_description>

Comments on the Issue (you are @copilot in this section)

@sfmskywalker This should be much better with 3.5.0 (currently in RC)

• Fixes Error when trying to view a workflow instance #6731

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