Problem: coder/license is a proof of concept and needs to be brought into spec with the [RFC](https://www.notion.so/coderhq/Workspaces-v2-Paid-Features-Licensing-45c00200adc64c19b0ae51bee7d32413#a1c78de1c0944af78fac029b46090d92). AC: 1. Generate a license with the licensor 1. Verify it is a JWT and can be validated with the public key 1. Verify it contains the fields in the RFC. Note: automated unit testing is generally not required for this repo