Add ServiceChannel to README (#617)

Add ServiceChannel in table of providers.

Author: dev-hyang

README.md

@@ -171,6 +171,7 @@ If a provider you're looking for does not exist, consider making a PR to add one
 | QuickBooks | [![NuGet](https://buildstats.info/nuget/AspNet.Security.OAuth.QuickBooks?includePreReleases=false)](https://www.nuget.org/packages/AspNet.Security.OAuth.QuickBooks/ "Download AspNet.Security.OAuth.QuickBooks from NuGet.org") | [![MyGet](https://buildstats.info/myget/aspnet-contrib/AspNet.Security.OAuth.QuickBooks?includePreReleases=true)](https://www.myget.org/feed/aspnet-contrib/package/nuget/AspNet.Security.OAuth.QuickBooks "Download AspNet.Security.OAuth.QuickBooks from MyGet.org") | [Documentation](https://www.developer.intuit.com/app/developer/qbo/docs/develop/authentication-and-authorization/oauth-2.0-playground "QuickBooks developer documentation") |
 | Reddit | [![NuGet](https://buildstats.info/nuget/AspNet.Security.OAuth.Reddit?includePreReleases=false)](https://www.nuget.org/packages/AspNet.Security.OAuth.Reddit/ "Download AspNet.Security.OAuth.Reddit from NuGet.org") | [![MyGet](https://buildstats.info/myget/aspnet-contrib/AspNet.Security.OAuth.Reddit?includePreReleases=true)](https://www.myget.org/feed/aspnet-contrib/package/nuget/AspNet.Security.OAuth.Reddit "Download AspNet.Security.OAuth.Reddit from MyGet.org") | [Documentation](https://github.com/reddit-archive/reddit/wiki/oauth2 "Reddit developer documentation") |
 | Salesforce | [![NuGet](https://buildstats.info/nuget/AspNet.Security.OAuth.Salesforce?includePreReleases=false)](https://www.nuget.org/packages/AspNet.Security.OAuth.Salesforce/ "Download AspNet.Security.OAuth.Salesforce from NuGet.org") | [![MyGet](https://buildstats.info/myget/aspnet-contrib/AspNet.Security.OAuth.Salesforce?includePreReleases=true)](https://www.myget.org/feed/aspnet-contrib/package/nuget/AspNet.Security.OAuth.Salesforce "Download AspNet.Security.OAuth.Salesforce from MyGet.org") | [Documentation](https://developer.salesforce.com/docs/atlas.en-us.api_rest.meta/api_rest/intro_understanding_web_server_oauth_flow.htm "Salesforce developer documentation") |
+| ServiceChannel | [![NuGet](https://buildstats.info/nuget/AspNet.Security.OAuth.ServiceChannel?includePreReleases=false)](https://www.nuget.org/packages/AspNet.Security.OAuth.ServiceChannel/ "Download AspNet.Security.OAuth.ServiceChannel from NuGet.org") | [![MyGet](https://buildstats.info/myget/aspnet-contrib/AspNet.Security.OAuth.ServiceChannel?includePreReleases=true)](https://www.myget.org/feed/aspnet-contrib/package/nuget/AspNet.Security.OAuth.ServiceChannel "Download AspNet.Security.OAuth.ServiceChannel from MyGet.org") | [Documentation](https://developer.servicechannel.com/basics/general/authentication "ServiceChannel developer documentation") |
 | Shopify | [![NuGet](https://buildstats.info/nuget/AspNet.Security.OAuth.Shopify?includePreReleases=false)](https://www.nuget.org/packages/AspNet.Security.OAuth.Shopify/ "Download AspNet.Security.OAuth.Shopify from NuGet.org") | [![MyGet](https://buildstats.info/myget/aspnet-contrib/AspNet.Security.OAuth.Shopify?includePreReleases=true)](https://www.myget.org/feed/aspnet-contrib/package/nuget/AspNet.Security.OAuth.Shopify "Download AspNet.Security.OAuth.Shopify from MyGet.org") | [Documentation](https://help.shopify.com/en/api/getting-started/authentication/oauth "Shopify developer documentation") |
 | Slack | [![NuGet](https://buildstats.info/nuget/AspNet.Security.OAuth.Slack?includePreReleases=false)](https://www.nuget.org/packages/AspNet.Security.OAuth.Slack/ "Download AspNet.Security.OAuth.Slack from NuGet.org") | [![MyGet](https://buildstats.info/myget/aspnet-contrib/AspNet.Security.OAuth.Slack?includePreReleases=true)](https://www.myget.org/feed/aspnet-contrib/package/nuget/AspNet.Security.OAuth.Slack "Download AspNet.Security.OAuth.Slack from MyGet.org") | [Documentation](https://api.slack.com/docs/oauth "Slack developer documentation") |
 | SoundCloud | [![NuGet](https://buildstats.info/nuget/AspNet.Security.OAuth.SoundCloud?includePreReleases=false)](https://www.nuget.org/packages/AspNet.Security.OAuth.SoundCloud/ "Download AspNet.Security.OAuth.SoundCloud from NuGet.org") | [![MyGet](https://buildstats.info/myget/aspnet-contrib/AspNet.Security.OAuth.SoundCloud?includePreReleases=true)](https://www.myget.org/feed/aspnet-contrib/package/nuget/AspNet.Security.OAuth.SoundCloud "Download AspNet.Security.OAuth.SoundCloud from MyGet.org") | [Documentation](https://developers.soundcloud.com/docs#authentication "SoundCloud developer documentation") |