Change whether this contact belongs to the personal group or not.
The personal contact group is a concept that exists only in Google address books. Other backends will throw a PropertyError.
It's preferred to call this rather than setting Persona.in_google_personal_group directly, as this method gives error notification and will only return once the membership has been written to the relevant backing store (or the operation's failed).
| in_personal | Whether to add or remove the personal group membership | 
| PropertyError | if the address book is not Google, or if setting the property failed | 
0.9.0