OAUTHBEARER sasl.mechanism not supported in AdminClient

[sverch]

Desired Outcome

I can use the AdminClient with the OAUTHBEARER sasl.mechanism.

Current State

Only the producer and consumer clients work with the OAUTHBEARER sasl.mechanism.

Background

I'm using the AdminClient struct and trying to get it working with the OAUTHBEARER sasl.mechanism. This project has producer and consumer examples, but it doesn't seem to work with the AdminClient.

I found that Client::poll_event handles the relevant event, but the AdminClient does not call that function. I tried to make the AdminClient call Client::poll_event, but I don't seem to get any events back, even after registering them with rd_kafka_conf_set_events. There's some difference between AdminClient and the producer client that I'm missing.