chore: enforce that r.Auth.Basic is nil when ecr auth is used

pkg/services/validator/oci.go

@@ -77,6 +77,7 @@ func configureAuth(r *plug.OciRegistryRule) error {
 	if r.Auth.ECR == nil {
 		r.Auth.ECR = &plug.ECRAuth{}
 	}
+	r.Auth.Basic = nil
 
 	accessKeyId, secretAccessKey, sessionToken, err := readAwsCreds(r.Auth.ECR.AccessKeyID, r.Auth.ECR.SecretAccessKey, r.Auth.ECR.SessionToken)
 	if err != nil {