Keystone transaction rejection UI translation

[LukasKorba]

Please, translate these 4 values to Spanish, thx

"keystoneTransactionReject.title" = "Are you sure?";
"keystoneTransactionReject.msg" = "Rejecting the signature will cancel the transaction, and you’ll need to start over if you want to proceed. This action cannot be undone.";
"keystoneTransactionReject.goBack" = "Go back";
"keystoneTransactionReject.rejectSig" = "Reject Signature";