Store a PEM certificate in service metadata

How could I store a PEM certificate in the service metadata, I am using something like this:

meta = {
    key = "-----BEGIN RSA PRIVATE KEY-----
MIIEogIBAAKCAQEA8pWof+Ys5ZY1ZtF2Bd+M6+CB0Q8rEW9eYCepynOBCh06RYfE
...
xUazSBE9hc9xaC6XXudKue2Hc4jyFhxQGcWZtIsaQZYEHwpWgGirdjYB7Ujzqs/w
xjnJ+Xyp7jJcE4DNIaioGcVXJw//UNO4e3HXsy6V8Cq9NN6I69k=
-----END RSA PRIVATE KEY-----
"
}

But I am getting erros like:

failed to parse /etc/consul.d/test.hcl: At 13:43: literal not terminated

Any ideas?