message: CustomSelect: fix popupDirectionTop styles
diff: border-color: var(--field_border);
  }
  -.CustomSelect__open .FormField__border {
  +.CustomSelect__open:not(.CustomSelect__open--popupDirectionTop) .FormField__border {
  border-bottom-left-radius: 0;
  border-bottom-right-radius: 0;
  }
  -.CustomSelect__open--popupDirectionTop .FormField__border {
  +.CustomSelect__open.CustomSelect__open--popupDirectionTop .FormField__border {
  border-top-left-radius: 0;
  border-top-right-radius: 0;
  }
  