Update to controller-runtime v0.16+

[blakebarnett]

Why is this needed: Big performance improvements for clusters with many CRDs installed via the new lazy restmapper client.

kubernetes-sigs/controller-runtime#2116

There are some breaking changes though:

https://github.com/kubernetes-sigs/controller-runtime/releases/tag/v0.15.0

[porridge]

We should be careful about the (unintended?) semantic incompatibilities such as:

• kubernetes-sigs/controller-runtime#2354