A new CLI command with the following syntax:

dns-cli get-active-group --provider-ref=<ref> zoneRootHost

• provider-ref: a secret in the current kubectl context cluster, granting access to the DNS provider.
• zoneRootHost: the root host of a zone, to identify which zone to interact with.

Expected:
Updates all zones that are an exact match for provided zoneRootHost.
Output all zones that were matched.
Test to ensure all zones are found and output as expected.

Output the list of groups - separated as a list, for example:

- ZoneID1:
  - group 1
  - group 2
- ZoneID2:
  - group 1
  - group 2
- ZoneID3: 
  - No active groups found