Enforce HTTP for Add Node operation

It's been discovered that tls verification can fail between Couchbase Servers due to a nuanced encoding issue in X.509 certificates for the Authority Key Identifier extension. 

In order to bypass this verification the Operator will need to add the Couchbase node as http.  This is insecure and supported only when directed by technical support/engineering but unblocks affected users who are upgrading from 6.5.0-7.0x to 7.1.0.