Race condition in `promote.yml` causes deploys to be skipped

## Use Case

Currently, the `deploy.yml` action triggers on any pushes to the `main` branch, and writes to the staging bucket.

The `promote.yml` action triggers on new tags pushed to `main`, and copies the contents of the staging bucket to the production bucket.

When a new commit with a release tag is made, both of these actions trigger at the same time, and `promote.yml` usually completes before `deploy.yml` can build and write to the staging bucket. This causes a race condition where the release made in the production bucket is one version out of date.

## Solution

Chain the `deploy.yml` and `promote.yml` actions together, possibly by making them part of the same action, to prevent the race condition.

## Alternatives

_Please describe any alternatives you've considered, even if you've dismissed them_