Start rename of "metrics server" config

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What does this MR do?

Rename the "metrics server" to "listen address"

Why was this MR needed?

"metrics server" is confusing for users as it implies this is a push target, not a polling listener.

Are there points in the code the reviewer needs to double check?

Does this MR meet the acceptance criteria?

• Documentation created/updated
• Tests
  • Added for this feature/bug
  • All builds are passing
• Branch has no merge conflicts with master (if you do - rebase it please)

What are the relevant issue numbers?