Avoid key prompts when resetting crypto (#4586)
* Avoid key prompts when resetting crypto
Attempting to get the backup key out of secret storage can cause
the user to be prompted for their key, which is not helpful if this
is being done as part of a reset. This check was redundant anyway
and we can just overwrite the key with the same value.
Also fix docs and remove check for active backup.
* Fix doc
