Environment variables override .databrickscfg, that's why it is probably failing to OIDC.

Make sure that you have correct specification in your databricks.yml so it will be source of true. Smth like:

- name: Deploy bundle
  env:
    DATABRICKS_HOST: https://adb-***.azuredatabricks.net
    ARM_TENANT_ID: ${{ secrets.AZURE_TENANT_ID }}
    ARM_CLIENT_ID: ${{ secrets.AZURE_CLIENT_ID }}
    ARM_CLIENT_SECRET: ${{ secrets.AZURE_CLIENT_SECRET }}