Pontoon/GUI: Update Latinamerican Spanish (es-419)

Co-authored-by: MaxEvil <xicovalle@gmail.com> (es-419)

Author: SlimeVR-bot

gui/public/i18n/es-419/translation.ftl

@@ -976,6 +976,9 @@ onboarding-setup_warning-cancel = Continuar configuración
 
 ## Quiz
 
+onboarding-quiz_continue = Continuar
+onboarding-quiz_back = Atrás
+onboarding-quiz-more_sets_modal-title = ¿Has conectado todos tus trackers?
 
 ## Wi-Fi setup