cleanup warnings

Author: ch1seL

samples/MessageSenderService/Worker.cs

@@ -75,7 +75,7 @@ private async Task<ulong> GetSentMessagesCount(IPackage contract, KeyPair keys,
 			Message = getCountEncodedMessage.Message
 		}, cancellationToken);
 
-		return result.Decoded.Output.Get<string>("c").HexToDec();
+		return result.Decoded.Output!.Get<string>("c").HexToDec();
 	}
 
 	private async Task SendMessage(IPackage senderContract, IPackage receiverContract, KeyPair keys,

src/EverscaleNet.AppKit/Exceptions/AccountDoesNotExistException.cs

@@ -3,4 +3,4 @@ namespace EverscaleNet.Exceptions;
 /// <summary>
 ///     Throws if call not deployed contract
 /// </summary>
-public class AccountDoesNotExistException : Exception { }
+public class AccountDoesNotExistException : Exception;

src/EverscaleNet.AppKit/Exceptions/AccountIsNotActiveException.cs

@@ -3,4 +3,4 @@ namespace EverscaleNet.Exceptions;
 /// <summary>
 ///     Throws if access to not active contract
 /// </summary>
-public class AccountIsNotActiveException : Exception { }
+public class AccountIsNotActiveException : Exception;

src/EverscaleNet.AppKit/Exceptions/AccountNotInitializedException.cs

@@ -3,4 +3,4 @@ namespace EverscaleNet.Exceptions;
 /// <summary>
 ///     Throws if access to not initialized contract
 /// </summary>
-public class AccountNotInitializedException : Exception { }
+public class AccountNotInitializedException : Exception;

src/EverscaleNet.Client/PackageManager/FilePackageManagerOptions.cs

@@ -2,4 +2,4 @@ namespace EverscaleNet.Client.PackageManager;
 
 /// <summary>
 /// </summary>
-public class FilePackageManagerOptions : PackageManagerOptions { }
+public class FilePackageManagerOptions : PackageManagerOptions;

src/EverscaleNet/Abstract/IEverModule.cs

@@ -3,4 +3,4 @@
 /// <summary>
 ///     Use for register modules by reflection
 /// </summary>
-public interface IEverModule { }
+public interface IEverModule;

tests/EverscaleNet.Client.Tests/ParallelRequestsTests.cs

@@ -1,7 +1,7 @@
 namespace EverscaleNet.Client.Tests;
 
 [CollectionDefinition(nameof(SystemTestCollectionDefinition), DisableParallelization = true)]
-public class SystemTestCollectionDefinition { }
+public class SystemTestCollectionDefinition;
 
 [Collection(nameof(SystemTestCollectionDefinition))]
 public class ParallelRequestsTests : IClassFixture<EverClientTestsFixture> {