Can you use GitHub Secrets in application.yaml or can it only be used in the Workflow file?

Question

I want to store DB credentials in GitHub secrets. Wondering if they can be used like so:

 datasource:
    url: db_name
    username: ${{ secrets.username }}
    password: ${{ secrets.password }}

Or will the secrets only work in the workflow files? Is there a way to get the secrets into my application.yaml file?