Rewrite JwtBearer TokenValidation Test

[JunTaoLuo]

Currently the test is using a token generated on AAD which means that the token will expire every 60 days (or some set interval). For this unit test, we should use a statically generated token that does not expire and not depend on an external authentication authority.

Security/test/Microsoft.AspNetCore.Authentication.Test/JwtBearerTests.cs

Lines 435 to 450 in bbff105

	[ConditionalFact(Skip = "Need to remove dependency on AAD since the generated tokens will expire")]
	[FrameworkSkipCondition(RuntimeFrameworks.Mono)]
	// https://github.com/AzureAD/azure-activedirectory-identitymodel-extensions-for-dotnet/issues/179
	public async Task BearerTokenValidation()
	{
	var server = CreateServer(o =>
	{
	o.Authority = "https://login.windows.net/tushartest.onmicrosoft.com";
	o.Audience = "https://TusharTest.onmicrosoft.com/TodoListService-ManualJwt";
	o.TokenValidationParameters.ValidateLifetime = false;
	});
	var newBearerToken = "Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsIng1dCI6ImtyaU1QZG1Cdng2OHNrVDgtbVBBQjNCc2VlQSJ9.eyJhdWQiOiJodHRwczovL1R1c2hhclRlc3Qub25taWNyb3NvZnQuY29tL1RvZG9MaXN0U2VydmljZS1NYW51YWxKd3QiLCJpc3MiOiJodHRwczovL3N0cy53aW5kb3dzLm5ldC9hZmJlY2UwMy1hZWFhLTRmM2YtODVlNy1jZTA4ZGQyMGNlNTAvIiwiaWF0IjoxNDE4MzMwNjE0LCJuYmYiOjE0MTgzMzA2MTQsImV4cCI6MTQxODMzNDUxNCwidmVyIjoiMS4wIiwidGlkIjoiYWZiZWNlMDMtYWVhYS00ZjNmLTg1ZTctY2UwOGRkMjBjZTUwIiwiYW1yIjpbInB3ZCJdLCJvaWQiOiI1Mzk3OTdjMi00MDE5LTQ2NTktOWRiNS03MmM0Yzc3NzhhMzMiLCJ1cG4iOiJWaWN0b3JAVHVzaGFyVGVzdC5vbm1pY3Jvc29mdC5jb20iLCJ1bmlxdWVfbmFtZSI6IlZpY3RvckBUdXNoYXJUZXN0Lm9ubWljcm9zb2Z0LmNvbSIsInN1YiI6IkQyMm9aMW9VTzEzTUFiQXZrdnFyd2REVE80WXZJdjlzMV9GNWlVOVUwYnciLCJmYW1pbHlfbmFtZSI6Ikd1cHRhIiwiZ2l2ZW5fbmFtZSI6IlZpY3RvciIsImFwcGlkIjoiNjEzYjVhZjgtZjJjMy00MWI2LWExZGMtNDE2Yzk3ODAzMGI3IiwiYXBwaWRhY3IiOiIwIiwic2NwIjoidXNlcl9pbXBlcnNvbmF0aW9uIiwiYWNyIjoiMSJ9.N_Kw1EhoVGrHbE6hOcm7ERdZ7paBQiNdObvp2c6T6n5CE8p0fZqmUd-ya_EqwElcD6SiKSiP7gj0gpNUnOJcBl_H2X8GseaeeMxBrZdsnDL8qecc6_ygHruwlPltnLTdka67s1Ow4fDSHaqhVTEk6lzGmNEcbNAyb0CxQxU6o7Fh0yHRiWoLsT8yqYk8nKzsHXfZBNby4aRo3_hXaa4i0SZLYfDGGYPdttG4vT_u54QGGd4Wzbonv2gjDlllOVGOwoJS6kfl1h8mk0qxdiIaT_ChbDWgkWvTB7bTvBE-EgHgV0XmAo0WtJeSxgjsG3KhhEPsONmqrSjhIUV4IVnF2w";
	var response = await SendAsync(server, "http://example.com/oauth", newBearerToken);
	Assert.Equal(HttpStatusCode.OK, response.Response.StatusCode);
	}

[Eilon]

Ideally we would mock away this logic and rewrite the test to avoid these stricter checks.