* NET-6945 - Replace usage of deprecated Envoy field envoy.config.core.v3.HeaderValueOption.append
* update proto for v2 and then update xds v2 logic
* add changelog
* Update 20078.txt to be consistent with existing changelog entries
* swap enum values tomatch envoy.
* NET-6946 - Replace usage of deprecated Envoy field envoy.config.route.v3.HeaderMatcher.safe_regex_match
* removing unrelated changes
* update golden files
* do not set engine type
When a large number of upstreams are configured on a single envoy
proxy, there was a chance that it would timeout when waiting for
ClusterLoadAssignments. While this doesn't always immediately cause
issues, consul-dataplane instances appear to consistently drop
endpoints from their configurations after an xDS connection is
re-established (the server dies, random disconnect, etc).
This commit adds an `xds_fetch_timeout_ms` config to service registrations
so that users can set the value higher for large instances that have
many upstreams. The timeout can be disabled by setting a value of `0`.
This configuration was introduced to reduce the risk of causing a
breaking change for users if there is ever a scenario where endpoints
would never be received. Rather than just always blocking indefinitely
or for a significantly longer period of time, this config will affect
only the service instance associated with it.
John Murret