Remove unused variables

Author: CarlosLanderas

src/JWTSimpleServer/JwtSimpleServerOptions.cs

@@ -11,9 +11,6 @@ public class JwtSimpleServerOptions
  public string Issuer { get; set; } = Constants.DefaultIssuer;
  public string IssuerSigningKey { get; set; }
  public Func<DateTime> NotBefore = () => DateTime.UtcNow;
- public Func<DateTime> Expires = () => DateTime.UtcNow.AddMinutes(15); 
- public void UseRefreshToken() => _UseRefreshToken = true; 
-
- private bool _UseRefreshToken = false;
+ public Func<DateTime> Expires = () => DateTime.UtcNow.AddMinutes(15); 
  }
 }