proposals-{proposal-id}-upgrades

Number of APIs: 3

1. Adds a new upgrade agreement to the proposal. POST {{baseUrl}}/proposals/:proposal-id/upgrades

2. Removes the upgrade agreement from the proposal. DELETE {{baseUrl}}/proposals/:proposal-id/upgrades/:upgrade-id

3. Get the upgrade agreements available for this proposal. GET {{baseUrl}}/proposals/:proposal-id/upgrades