crane: Can't be used with mTLS/CBA/ECP enabled accounts

### Describe the bug

crane doesn't seem to support mTLS ([ECP/CBA](https://cloud.google.com/chrome-enterprise-premium/docs/enable-cba-enterprise-certificates)) for GCR. Seems like the decision to use a custom library implementation for interacting with the APIs instead of relying on google.golang.org/api is the culprit.

### To Reproduce

Try to push or pull from gcr.io with an account enrolled in CBA.

### Expected behavior

Using crane works as it used to.

### Additional context

- Version: 0.20.6
- Registry used: GCR
- Account with CBA required
- Google API go package implementations:
- https://github.com/googleapis/google-api-go-client/tree/v0.248.0/internal/cert
- https://github.com/googleapis/google-api-go-client/blob/v0.248.0/internal/cba.go
- https://github.com/googleapis/google-api-go-client/blob/v0.248.0/transport/http/dial.go#L39