add_rejection
Description:
Add a pending reason for rejection.
The first call to this method is considered "most important". After calling this method as many times as are required, call reject_async to reject the certificate.
If details is a floating reference (see g_variant_ref_sink), ownership of details is taken by this
      function. This means you can pass the result of Variant or 
      Variant.parsed directly to this function without additional
      reference-count management.
Parameters:
| this | 
           a TLS certificate  | 
      
| reason | 
           the reason for rejection  | 
      
| dbus_error | 
           a D-Bus error name such as   | 
      
| details | 
           a variant of type VARDICT containing the details of the rejection, or
              |