Remove redundant #nullable enable (#4275)

Content.Server/Database/ServerBanDef.cs

@@ -3,7 +3,6 @@ using System.Collections.Immutable;
 using System.Net;
 using Robust.Shared.Network;
 
-#nullable enable
 
 namespace Content.Server.Database
 {

Content.Server/Database/ServerDbBase.cs

@@ -1,4 +1,3 @@
-#nullable enable
 using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;

Content.Server/Database/ServerDbManager.cs

@@ -21,7 +21,6 @@ using Robust.Shared.Network;
 using LogLevel = Robust.Shared.Log.LogLevel;
 using MSLogLevel = Microsoft.Extensions.Logging.LogLevel;
 
-#nullable enable
 
 namespace Content.Server.Database
 {

Content.Server/Database/ServerDbPostgres.cs

@@ -9,7 +9,6 @@ using System.Threading.Tasks;
 using Microsoft.EntityFrameworkCore;
 using Robust.Shared.Network;
 
-#nullable enable
 
 namespace Content.Server.Database
 {

Content.Server/Database/ServerDbSqlite.cs

@@ -16,7 +16,6 @@ using Robust.Shared.Configuration;
 using Robust.Shared.IoC;
 using Robust.Shared.Network;
 
-#nullable enable
 
 namespace Content.Server.Database
 {