Allow to configure hash ring via common config block

I proposed to deprecated consul and etcd for the KV store but apparently we're not ready to move everyone to memberlist yet. For the people still using etcd or consul backend, we could simplify their config adding support to configure the hash ring KV store via the common config block.

I propose the following config:

common:
  ring:
    kvstore:
      store: <string>
      consul: <consul>
      etcd: <etcd>
    instance_id: <string>
    instance_interface_names: <list of strings>
    instance_port: <int>
    instance_addr: <string>
    heartbeat_period: <duration>
    heartbeat_timeout: <duration>

Other fields I intentionally excluded because it's not safe to set the same value everywhere:

• ring.kvstore.prefix
• Replication factor

Notes:

• To add heartbeat_period to common we need to change all defaults to the same value first (addressed in https://github.com/grafana/mimir/pull/3033)