KES dependency upgrade (#14454)

- Updating KES dependency to v.0.18.0
- Fixing incompatibility issue when checking for errors during KES key creation

Signed-off-by: Lenin Alevski <alevsk.8772@gmail.com>

internal/kms/kes.go

@@ -22,6 +22,7 @@ import (
 	"crypto/tls"
 	"crypto/x509"
 	"errors"
+	"net/http"
 	"time"
 
 	"github.com/minio/kes"
@@ -140,3 +141,10 @@ func (c *kesClient) DecryptKey(keyID string, ciphertext []byte, ctx Context) ([]
 	}
 	return c.client.Decrypt(context.Background(), keyID, ciphertext, ctxBytes)
 }
+
+// KeyExists returns if key exists on KMS based on the provided error type
+func KeyExists(err error) bool {
+	// legacyKeyExists will be used to maintain compatibility with KES versions older than v0.18.0
+	legacyKeyExists := kes.NewError(http.StatusBadRequest, "key does already exist")
+	return errors.Is(err, kes.ErrKeyExists) || errors.Is(err, legacyKeyExists)
+}