Update account id mismatch error message for aws auth (#1934)

Author: vishalbollu

pkg/operator/endpoints/errors.go

@@ -77,7 +77,7 @@ func ErrorAuthInvalid() error {
 func ErrorAuthOtherAccount() error {
 	return errors.WithStack(&errors.Error{
 		Kind:    ErrAuthOtherAccount,
-		Message: "the AWS account associated with your CLI's AWS credentials differs from the AWS account associated with your cluster's AWS credentials; run `cortex env configure` to configure your environment with credentials for any IAM user in the same AWS account as your cluster",
+		Message: "the AWS account associated with your CLI's AWS credentials differs from the AWS account associated with your cluster's AWS credentials; run `aws sts get-caller-identity` to view the credentials being used by the cortex client",
 	})
 }