Test ClassLoader fails to load extension configuration #49684
Description
Describe the bug
When running a QuarkusTest using gradle along with an extension project the BuildTimeConfig and RuntimeConfig causes an issue (No config found for " + clazz).
I suspect this is due to the test classloader. I can see the config classes are in the BuildTimeConfigReader (objectsByClass) but I think the config classes are loaded in different classloaders so it won't find it by class in the map.
Expected behavior
Using an extension from source would work with Quarkustest
Actual behavior
The ExtensionLoader fails with No config found for interface at io.quarkus.deployment.configuration.BuildTimeConfigurationReader$ReadResult.requireObjectForClass
How to Reproduce?
Use a multimodule gradle project with an extension module and create a QuarkusTest. The test will fail with the configuration values although the app runs fine/
Output of uname -a or ver
Darwin MacBook-Pro.local 24.6.0 Darwin Kernel Version 24.6.0: Mon Jul 14 11:30:30 PDT 2025; root:xnu-11417.140.69~1/RELEASE_ARM64_T6020 arm64
Output of java -version
openjdk version "21.0.5" 2024-10-15 LTS
Quarkus version or git rev
3.25.4
Build tool (ie. output of mvnw --version or gradlew --version)
gradle 8.14
Additional information
Here's a small reproducer.