Customize OIDC audience

Spacelift’s OIDC tokens always have their audience set to your Spacelift hostname. However, many OIDC consumers require that they be able to set their own audience. Such consumers work on HCP Terraform because it allows you to set TFC_WORKLOAD_IDENTITY_AUDIENCE [1] to customize the token’s audience, but Spacelift offers no such feature.

[1] https://developer.hashicorp.com/terraform/cloud-docs/dynamic-provider-credentials/manual-generation