The algorithm of a Cloud KMS CryptoKeyVersion of a
CryptoKey with the
CryptoKeyPurpose
value ASYMMETRIC_SIGN. These values correspond to the
CryptoKeyVersionAlgorithm
values. For RSA signing algorithms, the PSS algorithms should be
preferred, use PKCS1 algorithms if required for compatibility. For
further recommandations, see
https://cloud.google.com/kms/docs/algorithms#algorithm_recommendations.