fixed wrong comment

[brah-mcdude]

The old comment that I previously wrote in ("we are not returning anything") was based on an old variable name that threw me off.
Here is the old code with the old variable name:

                probe.ReceiveWhile<object>(max: max, shouldIgnore: x =>
                {
                    x.Should().NotBeOfType<T>();
                    return false; // we are not returning anything
                });

When I looked into the code of the method ReceiveWhile(), I realized that "shouldIgnore" was a misleading variable name.
So I changed it to "shouldContinue" which much better reflects the code and the docs around it.

But I did not update the comment: "we are not returning anything".

So now, it is time to update the comment as well.
The new comment is: "please continue receiving, don't stop".
Which much better reflects the code and the variable name ("shouldContinue").

[Aaronontheweb]

Thanks!