quarkus.kubernetes.namespace property shouldn't provoke overriding of already set namespaces on resources

[metacosm]

Describe the bug

While not widely used at this time, it is possible for extensions to create additional / modify existing resources. It might happen that such resources need to be created in a different namespace than the one where most of the resources created by the Kubernetes extension (Deployment, Service, etc.) use. AddNamespaceDecorator, which handles the quarkus.kubernetes.namespace property, currently override any present namespace, thus potentially causing issues when extensions expect namespaces they set to remain untouched.

Expected behavior

If an extension sets a namespace on a resource, it is rather safe to assume that this value should be preserved and should therefore be left untouched when using quarkus.kubernetes.namespace.

Actual behavior

All namespaces are overridden by the quarkus.kubernetes.namespace value. Additionally, even manually provided resources defined in src/main/kubernetes also see their namespaces overridden.

How to Reproduce?

No response

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

2.15.0

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

No response

Additional information

No response

[quarkus-bot]

/cc @Sgitario, @geoand, @iocanel