[cms] Misleading Politeia identity labels

[xaur]

The Account > Identity page says it is a Politeia identity which is not the case. Politeia and CMS have separate accounts with separate identities (key pairs) and UUIDs, even if the accounts are owned by the same person.

This seemed like a small cosmetic issue when I originally reported it in 2019 (#1196) but a chat with a new CMS user suggested it is more severe. This label may mislead a new user to believe they can skip the identity backup step because they have their Politeia identity already backed up.

Thanks to @nnnko56 for bringing up the issue.