[BestPractice] Complete the task associated to this 'TODO' comment.

[github-actions]

Codacy ID: eaec3c210bfcdba6a96abc8b9d791572

File: TransactionProcessor.BusinessLogic/Services/MerchantDomainService.cs
Line: 275
Rule: BestPractice (Warning)
Commit: 5b8f3e64d731c7b181b225e9d4117fda74faa3ac

Message: Complete the task associated to this 'TODO' comment.

**Code Snippet:**
```csharp
                // TODO: add a delete user here in case the aggregate add fails... 
```