It seems that "json" annotation fails to get dashed names (like
configmap-files). That means that all labels in katernay.yaml file
couldn't be parsed.
Using `yaml` annotaiton fixes the problem. Fixes#144.
Go 1.24 made several changes about formatting messages:
https://tip.golang.org/doc/go1.24#vet
These changes make tests (and vet) craching.
The fix is to use a string format and give error message as argument.
