[Bug]: Kafka Server startup failure with Keycloak authentication

[zzhu158]

Bug Description

I've encountered an issue when using compose-authz.yml with Keycloak OAuth server. The error message in the log shows that the POST request to get the OAuth token fails with a 404 status code:
[2024-03-20 21:39:29,536] DEBUG loginWithClientSecret() - tokenEndpointUrl: http://keycloak:8080/auth/realms/kafka-authz/protocol/openid-connect/token, clientId: kafka, clientSecret: k*********, scope: null, audience: null, connectTimeout: 60, readTimeout: 60, retries: 0, retryPauseMillis: 0 (io.strimzi.kafka.oauth.common.OAuthAuthenticator) kafka | [2024-03-20 21:39:29,557] INFO Action failed on try no. 1 (io.strimzi.kafka.oauth.common.HttpUtil) kafka | io.strimzi.kafka.oauth.common.HttpException: POST request to http://keycloak:8080/auth/realms/kafka-authz/protocol/openid-connect/token failed with status 404: {"error":"Unable to find matching target resource method"}
I checked to see if Keycloak was working properly, when clicking on the "Admin Console" it shows "Loading" but couldn't be completed.

Steps to reproduce

1. Go to examples/docker/kafka-oauth-strimzi/compose-authz.yml
2. run ```
   docker-compose -f compose.yml -f keycloak/compose.yml -f keycloak-import/compose.yml
   -f kafka-oauth-strimzi/compose-authz.yml up --build

3. Login to Keycloak, and clicking Keycloak Admin Console, it will show the issue.

[zzhu158]

Closed this issue. I opened the issue in strimzi-kafka-oauth