update steps to get fontawesome pro to work on fly deploy

I’m trying to adapt this article https://community.fly.io/t/fly-secrets-not-populated-during-build/659/15?u=dreday to use with the fly.toml and docker file generated when i setup my app.

I’m using a basic remix.run app and followed their deployment steps. All worked fine until i added fontawesome pro to my project.

has anyone successfully been able to deploy with the latest fontawesome pro? thanks