Bug: Keycloak health check not working with HTTP relative path #964

Describe the bug

In case a HTTP relative path is configured the health check requires to consider this relative path.
The Keycloak module does support port number and hard-coded health endpoint but not HTTP relative path during readiness probe (ie Keycloak health check).

(Related topic: With Keycloak version 26.3 the health endpoint is only provided via managament port but not other ports.)

To Reproduce

from testcontainers.keycloak import KeycloakContainer

keycloak = KeycloakContainer('quay.io/keycloak/keycloak:latest') \
        .with_env("KEYCLOAK_ADMIN", 'test') \
        .with_env("KEYCLOAK_ADMIN_PASSWORD", 'test') \
        .with_env("KC_HTTP_RELATIVE_PATH", "/auth") \
        .with_env("KC_HEALTH_ENABLED", 'true') \
        .with_env("KC_HTTP_MANAGEMENT_RELATIVE_PATH", "/auth") \
        .with_command("start-dev")

keycloak.start()

With this Keycloak Container the readiness probe is failing with HTTP error

requests.exceptions.HTTPError: 404 Client Error: Not Found for url: http://localhost:53741/health/ready

However, keycloak health check is successful when HTTP relative path is included,i.e. when the following request is used:

http://localhost:53741/auth/health/ready

For readiness probe in testcontainer please see
https://github.com/testcontainers/testcontainers-python/blob/main/modules/keycloak/testcontainers/keycloak/__init__.py#L89

Runtime environment

Windows System
python 3.13.3
docker 28.4.0
testcontainers-python 4.14.0