Touch call with CAS passed causes ERRO[0000] Touch: invalid arguments against Spock or higher

On behalf of Raymundo Flores, I'm filing this bug.

According to https://github.com/couchbase/kv_engine/blob/325854f8c9368a15c8f1f245e838d46fb3af0bfa/daemon/mcbp_validators.cc#L847, it is expected that none-zero CAS will return PROTOCOL_BINARY_RESPONSE_EINVAL from the server version 5.x
I checked Java, it does not ask for Cas on Touch operation. Also Sergy mentioned libcouchbase explicitly set cas to zero https://github.com/couchbase/libcouchbase/blob/9249c3cfe65226bae35bb3d91f05aa4cbcbd6ce4/src/operations/touch.cc#L43

Expected : Either Touch does not allow CAS in parameter or set CAS to zero explicitly so user does not face ERRO[0000] on Touch operation.
Actual : when none zero value is passed user sees ERRO[0000]

To reproduce, you need to test against 5.x server version. 4.x has no issue.