[Bug]: Failed to promote deployments when project is relinked to a different branch

### Problem description

When originally developing our repository's website to use Deploy, we first use the `www` branch. Later however, once the website was established, we went in and changed it to `main` by re-linking the project. However, because the next build would not happen until the next PR is merged, we wanted to promote the last PR build to production. However, when doing that, it reported an API error:

### Steps to reproduce

1. create project with one branch
2. re-link it to another
3. try to promote a prior deployment from the original branch to production.

### Expected behavior

1. It promotes the deployment
2. non-optimal (but preferable) is the "promote to production" menu option is disabled with a message something like "re-linked projects cannot promote older builds"

### Environment

Deno Deploy

### Possible solution

_No response_

### Additional context