Remove consul_consul from some metric namespaces

# Overview of the Issue

Some metrics in the `cache, fsm, and runtime` subcomponents emit write their namespace as `consul_consul...`. This is obviously wrong; as much as we love Consul we ought not name it twice where once will suffice!

#### Reproduction Steps

Start a connect-enabled 2-dc cluster on docker with https://github.com/mkeeler/consul-docker-test/tree/master/mesh-gateways-l7. The metrics can be queried for with `consul_consul` in prometheus' promql query runner.

### Operating system and Environment details

Linux, Docker

### Screenshots

View from inside the prometheus dashboard, querying for `consul_consul`