Bug/Use original_id of parent for new token original_id

[jonmattgray]

When multiple tokens are about the same thing e.g a PO, we want them all to have the same original_id. This PR changes the pallet to correctly assign original_id rather than the id of a parent to a new token's original_id.

e.g. assuming all these tokens are about the same thing, such as a Quote. This PR goes from this:
Token 1: id: 1 original_id: 1
Token 2: id: 2 original_id: 1
Token 3: id: 3 original_id: 2 // this is wrong

to this
Token 1: id: 1 original_id: 1
Token 2: id: 2 original_id: 1
Token 3: id: 3 original_id: 1 // this is correct

[mattdean-digicatapult]

Good catch. Note this introduces extra storage gets so weights should be updated