List NodeFeature and NodeResourceTopology objects in pages of 200 items.
This reduces memory consumption and eliminates timeouts (on the
apiserver side) in big clusters of thousands of nodes.
This change is part of an effort to remove the pkg/apihelper package.
GetKubeconfig is useful helper functionality shared accross the codebase
so move it into a "safe" location.
Implements three metrics for nfd-gc:
- nfd_gc_build_info: version information of nfd-gc.
- nfd_gc_objects_deleted_total: total number of NodeFeature and
NodeResourceTopology objects deleted by nfd-gc.
- nfd_gc_object_delete_failures_total: number of errors encountered when
deleting NodeFeature and NodeResourceTopology objects.
Hook into the same logic already exercised for NodeResourceTopology
objects: GC watches for node delete events and immediately drops stale
objects (NRT and now also NF). In addition there is a periodic resync to
catch any missed node deletes, once every hour by default.
