sharedSecretKey property
A base 32 encoded string that represents the shared TOTP secret.
The base 32 encoding is the one specified by [RFC4648#section-6](https://datatracker.ietf.org/doc/html/rfc4648#section-6). (This is the same as the base 32 encoding from [RFC3548#section-5](https://datatracker.ietf.org/doc/html/rfc3548#section-5).)
Implementation
core.String? sharedSecretKey;