Quarkus OpenId Connect Bearer Token Integration/Security Testing - quarkus

Question

I'm following https://quarkus.io/guides/security-openid-connect#integration-testing-wiremock to create some tests for my Quarkus app:
#QuarkusTest
#TestHTTPEndpoint(BannerApi.class)
#QuarkusTestResource(OidcWiremockTestResource.class)
public class BannerApiTest {
#Test
public void testListUnauthenticated() {
when().get().then().statusCode(401);
}
}
I followed the setup as-is, except I created application.properties in src/test/resources with the following contents:
quarkus.oidc.auth-server-url=${keycloak.url}/realms/quarkus/
quarkus.oidc.client-id=quarkus-service-app
quarkus.oidc.application-type=service
smallrye.jwt.sign.key.location=privateKey.jwk
But here's what I get:
2021-08-03 21:18:41,731 INFO [org.ecl.jet.uti.log] (pool-5-thread-1) Logging initialized #14312ms to org.eclipse.jetty.util.log.Slf4jLog
...
2021-08-03 21:18:42,041 INFO [io.qua.tes.oid.ser.OidcWiremockTestResource] (pool-5-thread-1) Keycloak started in mock mode: http://localhost:64289
...
2021-08-03 21:18:44,348 INFO [org.ecl.jet.ser.han.ContextHandler] (main) Stopped o.e.j.s.ServletContextHandler#520fdce4{/__admin,null,STOPPED}
2021-08-03 21:18:44,349 INFO [io.qua.tes.oid.ser.OidcWiremockTestResource] (main) Keycloak was shut down
java.lang.RuntimeException: java.lang.RuntimeException: Failed to start quarkus
at io.quarkus.test.junit.QuarkusTestExtension.throwBootFailureException(QuarkusTestExtension.java:686)
at io.quarkus.test.junit.QuarkusTestExtension.interceptTestClassConstructor(QuarkusTestExtension.java:759)
at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:106)
...
Caused by: java.lang.RuntimeException: Failed to start quarkus
at io.quarkus.runner.ApplicationImpl.doStart(ApplicationImpl.zig:1114)
at io.quarkus.runtime.Application.start(Application.java:101)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
... 31 more
Caused by: javax.enterprise.inject.spi.DeploymentException: Configuration validation failed:
keycloak.url does not map to any root
at io.quarkus.arc.runtime.ConfigRecorder.registerConfigMappings(ConfigRecorder.java:67)
at io.quarkus.deployment.steps.ConfigBuildStep$registerConfigClasses-2116437784.deploy_0(ConfigBuildStep$registerConfigClasses-2116437784.zig:292)
at io.quarkus.deployment.steps.ConfigBuildStep$registerConfigClasses-2116437784.deploy(ConfigBuildStep$registerConfigClasses-2116437784.zig:40)
... 46 more
Caused by: io.smallrye.config.ConfigValidationException: Configuration validation failed:
keycloak.url does not map to any root
at io.smallrye.config.ConfigMappingProvider.mapConfiguration(ConfigMappingProvider.java:829)
at io.smallrye.config.ConfigMappingProvider.mapConfiguration(ConfigMappingProvider.java:785)
at io.smallrye.config.ConfigMappings.mapConfiguration(ConfigMappings.java:54)
... 49 more
org.opentest4j.TestAbortedException: Boot failed
at io.quarkus.test.junit.QuarkusTestExtension.throwBootFailureException(QuarkusTestExtension.java:688)
at io.quarkus.test.junit.QuarkusTestExtension.interceptTestClassConstructor(QuarkusTestExtension.java:759)
at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:106)
...
As you can see from the log, Keycloak started in mock mode: http://localhost:64289 ... but then keycloak.url does not map to any root.
Where do I miss? I'm using Quarkus 2.1.0.