Link to related subscription from trial record when relevant
Background
Some trials are linked to an existing customer, such as:
- Existing GitLab.com Premium customer who initiates Ultimate trial
- [Coming soon] Existing GitLab.com Premium or Ultimate customer who initiates Duo Pro trial
However, the way these are setup today, we don't have any sort of link back to the related paid subscription info. Having this info would be useful to track conversin rates, ARR impact, etc.
Proposal
Add tracking of related subscription, when applicable to trial order.
Result
Ability to directly connect Subscription with trial data.