Few tweaks

Author: danielmarbach

src/NServiceBus.Transport.RabbitMQ/Connection/ChannelProvider.cs

@@ -84,10 +84,10 @@ protected virtual void FireAndForget(Func<CancellationToken, Task> action, Cance
 
         public async ValueTask<ConfirmsAwareChannel> GetPublishChannel(CancellationToken cancellationToken = default)
         {
-            while (true)
+            while (!cancellationToken.IsCancellationRequested)
             {
                 var existing = Interlocked.CompareExchange(ref publishChannel, null, null);
-                if (existing is not null && !existing.IsClosed)
+                if (existing is { IsOpen: true })
                 {
                     return existing;
                 }
@@ -114,7 +114,7 @@ public async ValueTask<ConfirmsAwareChannel> GetPublishChannel(CancellationToken
 
         public ValueTask ReturnPublishChannel(ConfirmsAwareChannel channel, CancellationToken cancellationToken = default)
         {
-            if (!channel.IsClosed)
+            if (channel.IsOpen)
             {
                 return ValueTask.CompletedTask;
             }