Update providers to .NET 6

Update the new providers from the 5.0.5 release to .NET 6.

src/AspNet.Security.OAuth.Notion/NotionAuthenticationHandler.cs

@@ -87,7 +87,7 @@ protected override async Task<AuthenticationTicket> CreateTicketAsync(
                 Options,
                 Backchannel,
                 tokens,
-                tokens.Response.RootElement);
+                tokens!.Response!.RootElement);
             context.RunClaimActions();
 
             await Options.Events.CreatingTicket(context);