build: run prepare before install in Dockerfile

[holic]

had this fix/workaround in CI but not in Dockerfile

[changeset-bot]

⚠️ No Changeset found

Latest commit: 80faacd

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[holic]

confirmed that this got past the install/build step:
https://github.com/latticexyz/mud/actions/runs/8160408709/job/22306926234

merging to fix main's docker release step