Auto-mocking Uni does not work in continuous testing, failing tests that work in normal testing

[famod]

Describe the bug

For normal testing (e.g. via surefire), MutiniyAnswer is auto-registered via a custom configuration, so that you don't have to stub e.g. ReactiveMailer.send(Mail) on your own.

In continuous testing though, this configuration is not present/found so that a test that is running fine via surefire will fail with an NPE in continuous testing.

Expected behavior

Same behavior as normal testing; auto-mocking takes place.

Actual behavior

Auto-mocking Uni doesn't work in cont' testing, a NPE will pop up failing the test.

How to Reproduce?

q_ct-mutinyanswer.zip

1. mvn clean verify (all tests should pass)
2. mvn clean quarkustest (all tests should fail)

This reproducer contains three slightly different tests to show that this is a general problem also affecting QuarkusTest.

Output of uname -a or ver

No response

Output of java -version

No response

GraalVM version (if different from Java)

No response

Quarkus version or git rev

2.6.3.Final, 2.7.0.CR1 and current 999-SNAPSHOT

Build tool (ie. output of mvnw --version or gradlew --version)

Maven 3.8.4

Additional information

https://quarkusio.zulipchat.com/#narrow/stream/187038-dev/topic/mockito.2Einternal.2EMutinyAnswer

This is probably related to how org.mockito.internal.configuration.ClassPathLoader is loading such a custom config and to #7872.

[quarkus-bot]

/cc @stuartwdouglas

[famod]

I have a fix for this, leveraging parent-first. It's not pretty but let's see what you say when I have created the PR (today or tomorrow).