Restassured Test Quarkus not running withing Docker Container - gitlab-ci

Question

I have a normal Quarkus Restassured Test working very fine locally on my workstation:
#Test
public void testHelloEndpoint() {
given()
.when().get("/ifc")
.then()
.statusCode(200)
.body(containsString("hello"));
}
however, when I run this on Gitlab CI withing a docker container from image image: maven:3.6.3-jdk-11 it hangs. I suppose, the Tests wants to connect to locahost:8081 internally of the container, which does not work.
How to solve this?
gitlab-ci:
image: maven:3.6.3-jdk-11
variables:
MAVEN_CLI_OPTS: "-s m2-settings.xml --batch-mode"
#MAVEN_CLI_OPTS: ""
MAVEN_OPTS: "-Dmaven.repo.local=.m2/repository"
cache:
paths:
#- .m2/repository/
#- target/
build:
stage: build
script:
- mvn $MAVEN_CLI_OPTS compile
test:
stage: test
script:
- java --version
- mvn $MAVEN_CLI_OPTS install
deploy:
stage: deploy
script:
- mvn $MAVEN_CLI_OPTS deploy
only:
- master
when: manual
When I run the same docker image locally (not gitlab) I see the following errors:
[ERROR] Tests run: 3, Failures: 0, Errors: 3, Skipped: 0, Time elapsed: 61.157 s <<< FAILURE! - in ch.siemens.bt.ifc.ResourceTest
[ERROR] testGenerateEndpoint Time elapsed: 0.073 s <<< ERROR!
java.lang.NoClassDefFoundError: Could not initialize class org.codehaus.groovy.reflection.ReflectionCache
[ERROR] testTransformEndpoint Time elapsed: 0.001 s <<< ERROR!
java.lang.NoClassDefFoundError: Could not initialize class io.quarkus.test.common.RestAssuredURLManager
[ERROR] testHelloEndpoint Time elapsed: 0.001 s <<< ERROR!
java.lang.NoClassDefFoundError: Could not initialize class io.quarkus.test.common.RestAssuredURLManager

Answer 1

I have realised that using the image quay.io/quarkus/centos-quarkus-maven:20.0.0-java11 works. I don't see why - because I am not doing native builds.