Remove reference to protocol in sink description

[jlurien]

Problem description

sink description includes a reference to the "selected protocol" but we are not including the protocol property

Expected behavior

Remove that reference or indicate explicitly that it must be HTTP:

"The address to which events shall be delivered using the selected protocol." -> "The address to which events shall be delivered." or "The address to which events shall be delivered, using the "HTTP" protocol."

Alternative solution

Add the protocol property as in the artifact to be prepared in the future to allow protocols other than HTTP, but this could be done in a future release. In this case it would be better to group all related properties under a new object, e.g. "notifications: { sink, sinkCredential, protocol, etc } and probably it would be good to indicate the model for implicit subscriptions more clearly in the guidelines.

Additional context

We may add the description fix to the PR #336, make a separate PR, merge it and then rebranch PR #336, or wait for rc.2

[jlurien]

@hdamker for your consideration

[hdamker]

@jlurien Within quality-on-demand we had addressed that already in #335. Have done now the alignment of the sink description between quality-on-demand and qod-provisioning within #336 and updated the PR description.

[hdamker]

Fixed in #336