[UnusedCode] Remove the unused local variable 'merchants'.

[github-actions]

Codacy ID: 6e4fbcdc6e3c6ca64e551a24f3c015cd

File: EstateReportingAPI.BusinessLogic/ReportingManager.cs
Line: 544
Rule: UnusedCode (Warning)
Commit: 5f2bfc8dec6178523dfd87cd5cc6ce0768f2bd01

Message: Remove the unused local variable 'merchants'.

**Code Snippet:**
```csharp
        var merchants = await context.Merchants.Select(m => new { m.Name, m.LastSaleDate, m.LastSaleDateTime }).ToListAsync(); 
```