Fix for issue dotnet#2073

signed-off-by: Whit Waldo <whit.waldo@innovian.net>

Rx.NET/Documentation/IntroToRx/02_KeyTypes.md

@@ -283,7 +283,7 @@ source.Subscribe(
 
 The overloads of `Subscribe` where we don't pass all three methods (e.g., my earlier example just supplied a single callback corresponding to `OnNext`) are equivalent to writing an `IObserver<T>` implementation where one or more of the methods simply has an empty body. Whether we find it more convenient to write our own type that implements `IObserver<T>`, or just supply callbacks for some or all of its `OnNext`, `OnError` and `OnCompleted` method, the basic behaviour is the same: an `IObservable<T>` source reports each event with a call to `OnNext`, and tells us that the events have come to an end either by calling `OnError` or `OnCompleted`.
 
-If you're wondering whether the relationship between `IObservable<T>` and `IObserver<T>` is similar to the relationship between [`IEnumerable<T>`](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.ienumerable-1) and [`IEnumerator<T>`](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.ienumerator-1), then you're onto something. Both `IEnumerator<T>` and `IObservable<T>` represent _potential_ sequences. With both of these interfaces, they will only supply data if we ask them for it. To get values out of an `IEnumerable<T>`, an `IEnumerator<T>` needs to come into existence, and similarly, to get values out of an `IObservable<T>` requires an `IObserver<T>`.
+If you're wondering whether the relationship between `IObservable<T>` and `IObserver<T>` is similar to the relationship between [`IEnumerable<T>`](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.ienumerable-1) and [`IEnumerator<T>`](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.ienumerator-1), then you're onto something. Both `IEnumerable<T>` and `IObservable<T>` represent _potential_ sequences. With both of these interfaces, they will only supply data if we ask them for it. To get values out of an `IEnumerable<T>`, an `IEnumerator<T>` needs to come into existence, and similarly, to get values out of an `IObservable<T>` requires an `IObserver<T>`.
 
 The difference reflects the fundamental _pull vs push_ difference between `IEnumerable<T>` and `IObservable<T>`. Whereas with `IEnumerable<T>` we ask the source to create an `IEnumerator<T>` for us which we can then use to retrieve items (which is what a C# `foreach` loop does), with `IObservable<T>`, the source does not _implement_ `IObserver<T>`: it expects _us_ to supply an `IObserver<T>` and it will then push its values into that observer.