Fix async code problems

src/Persistence/Wolverine.EntityFrameworkCore/Internals/TenantedDbContextBuilderByConnectionString.cs

@@ -65,8 +65,8 @@ public async ValueTask<T> BuildAndEnrollAsync(MessageContext messaging, Cancella
         var dbContext = _constructor(builder.Options);
 
         var transaction = new MappedEnvelopeTransaction(dbContext, messaging);
-        // ReSharper disable once MethodHasAsyncOverload
-        messaging.EnlistInOutbox(transaction);
+
+        await messaging.EnlistInOutboxAsync(transaction);
 
         return dbContext;
     }

src/Persistence/Wolverine.EntityFrameworkCore/Internals/TenantedDbContextBuilderByDbDataSource.cs

@@ -67,8 +67,7 @@ public async ValueTask<T> BuildAndEnrollAsync(MessageContext messaging, Cancella
         var dbContext = _constructor(builder.Options);
 
         var transaction = new MappedEnvelopeTransaction(dbContext, messaging);
-        // ReSharper disable once MethodHasAsyncOverload
-        messaging.EnlistInOutbox(transaction);
+        await messaging.EnlistInOutboxAsync(transaction);
 
         return dbContext;
     }

src/Persistence/Wolverine.RDBMS/Polling/DatabaseBatcher.cs

@@ -80,7 +80,7 @@ public async Task DrainAsync()
     {
         try
         {
-            _internalCancellation.Cancel();
+            await _internalCancellation.CancelAsync();
 
             _batchingBlock.Complete();
             await _batchingBlock.Completion;

src/Persistence/Wolverine.RDBMS/Transport/ExternalMessageTableListener.cs

@@ -89,12 +89,11 @@ public ValueTask DeferAsync(Envelope envelope)
         return new ValueTask();
     }
 
-    public ValueTask DisposeAsync()
+    public async ValueTask DisposeAsync()
     {
-        _cancellation.Cancel();
+        await _cancellation.CancelAsync();
 
         _task.SafeDispose();
-        return ValueTask.CompletedTask;
     }
 
     public Uri Address { get; }

src/Persistence/Wolverine.SqlServer/Transport/SqlServerQueueListener.cs

@@ -39,20 +39,17 @@ public async ValueTask DeferAsync(Envelope envelope)
         await _queue.SendAsync(envelope, _cancellation.Token);
     }
 
-    public ValueTask DisposeAsync()
+    public async ValueTask DisposeAsync()
     {
-        _cancellation.Cancel();
+        await _cancellation.CancelAsync();
         _task.SafeDispose();
         _scheduledTask.SafeDispose();
-        return ValueTask.CompletedTask;
     }
 
     public Uri Address => _queue.Uri;
-    public ValueTask StopAsync()
+    public async ValueTask StopAsync()
     {
-        _cancellation.Cancel();
-
-        return ValueTask.CompletedTask;
+        await _cancellation.CancelAsync();
     }
 
     private async Task lookForScheduledMessagesAsync()