REST API Endpoint "/controller/changePassword" is not documented in documentation for 7.1+

Was looking for methods for users to change their passwords without needing administrative roles. Couldn't find any on 7.1+ documentation as we were just led to using either /settings/rbac/users/local/<username>/ or having to use couchbase-cli-user-change-password.

Then found that in Couchbase UI, the password change feature uses the https://github.com/couchbase/ns_server/blob/8716fa28913b8b703e36acd1ac206d3ef679660c/priv/public/ui/app/mn_admin/mn_reset_password_dialog_service.js#L47 feature found here. Which gave us the rest api: /controller/changePassword/. We'd like this to be documented please.

Related Slack conversation: https://couchbase.slack.com/archives/CR3FMGTDX/p1693389760619209