Fix content.integration tests warnings (#17817)

Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>

Content.IntegrationTests/Tests/MachineBoardTest.cs

@@ -1,9 +1,7 @@
 using System.Collections.Generic;
 using System.Linq;
-using System.Threading.Tasks;
 using Content.Server.Construction.Components;
 using Content.Shared.Construction.Components;
-using NUnit.Framework;
 using Robust.Shared.Prototypes;
 
 namespace Content.IntegrationTests.Tests;