We lose the connection to the proposal when we edit a creation review

Step to reproduce:

1. Create a proposal
2. From the proposal page, create a Creation Review for the proposal
3. Edit the Creation Review
4. Click "Save"

The link to the proposal gets dropped.

The "Reference" field is used to keep track of the proposal or release record that is to be associated with the review record. That field has no entries in "edit" mode which assume is the reason why we lose that information.