Kubernetes extension should not use version in labelselectors

[brokenjacobs]

Describe the bug
When using manifests generated by the quarkus kubernetes extension, issues are encountered updating versions of deployed software. This is because labelselectors in deployments and other kubernetes objects are immutable. When using software such as fluxcd, the manifest is not able to be updated without deleting the old deployment, or naming the new deployment something else, as labelSelectors cannot be updated in a deployment manifest.

Expected behavior
LabelSelector will not include:
app.kubernetes.io/version

in the manifests generated

Actual behavior
app.kubernetes.io/version is included in the manifests

To Reproduce
Steps to reproduce the behavior:

1. Generate build for a versioned release.
2. Deploy the build to kubernetes
3. Generate a build for a new version
4. Try to apply manifests with kubectl apply. Observe failure due to immutable labelSelector.

[quarkusbot]

/cc @geoand

[brokenjacobs]

Slightly more nuanced here.. the labels that are used in the selector should be configurable.

[geoand]

I like the idea about the configurable labels in the selector.