Should respect cancellation token when waiting on connection lock.

[mikaelm12]

Waiting on the connection state lock in the HubConnection and HttpConnection should respect cancellation token

The WaitConnectionLockAsync method should take a cancellation token and pass it into the WaitAsync method.
https://github.com/aspnet/AspNetCore/blob/4921dc3aa3496eb3e9fe73255213ce54a0ba29d6/src/SignalR/clients/csharp/Client.Core/src/HubConnection.cs#L1926-L1930

We also need this in HttpConnection here
https://github.com/aspnet/AspNetCore/blob/4921dc3aa3496eb3e9fe73255213ce54a0ba29d6/src/SignalR/clients/csharp/Http.Connections.Client/src/HttpConnection.cs#L207

[analogrelay]

Let's do it in master. We talked through the cancellation impact and it should be fine.