Allow StreamClient to connect using UserSessionToken.

[ibebbs]

PR for issue 39.

Using this code I was able to retrieve feed activities using a client authenticated with a user session token as shown below:

// Executed on the server
var serverConnection = new StreamClient(apiKey, apiSecret);
var clientToken = serverConnection.CreateUserSessionToken(userId);

// Just to verify that the 'server' can retrieve the users feed
var serverResponse = await serverConnection.Feed(feedSlug, userId).GetActivities(); // executes correctly

display($"Activites retrieved on server: {serverResponse.Count()}");

var clientConnection = new StreamClient(apiKey, clientToken);
var clientResponse = await clientConnection.Feed(feedSlug, userId).GetActivities(); // previously failed with "signature is invalid" now succeeds

display($"Activites retrieved on client: {clientResponse.Count()}");

[ibebbs]

Looks like the CI build needs some environment variables set for credentials.

[ferhatelmas]

LGTM

Thanks for this PR 👍

[ferhatelmas]

Looks like the CI build needs some environment variables set for credentials.

@ibebbs secrets aren't exposed to PRs from users don't have write rights, due to security. Will be improved though while going for github action.

Thanks again!