Disable cAdvisor json Metrics

This KEP outlines the process to deprecate cAdvisor json metrics collected by Kubelet. This is one step towards removing cAdvisor APIs from the kubelet, which has been a long-time goal of sig-node. cAdvisor only supports linux, and only supports a small set of container runtimes. For that reason, sig-node has historically wanted to allow vendors to replace cAdvisor without paying a double-collection performance penalty. This hasn't been achieved yet, despite some incremental progress. This KEP is another small step towards that goal. Note that cAdvisor endpoints are not believed to be widely used. They were entirely broken for multiple releases before someone reported it: kubernetes/kubernetes#62544. This was originally part of the "metrics overhaul" KEP, but was removed because it had not been completed. There were also concerns raised about removing these metrics. cAdvisor json metrics were disabled by default starting in 1.18, and could be re-enabled by setting --enable-cadvisor-json-endpoints to true. However, given the concerns about removing the endpoints, we want to re-visit the deprecation and removal of these metrics before removing them permanently.