Automatic merge from submit-queue (batch tested with PRs 43429, 43416, 43312, 43141, 43421)

add singular resource names to discovery

Adds the singular resource name to our resource for discovery.  This is something we've discussed to remove our pseudo-pluralization library which is unreliable even for english and really has no hope of properly handling other languages or variations we can expect from TPRs and aggregated API servers.

This pull simply adds the information to discovery, it doesn't not re-wire any RESTMappers.

@kubernetes/sig-cli-misc  @kubernetes/sig-apimachinery-misc @kubernetes/api-review


```release-note
API resource discovery now includes the `singularName` used to refer to the resource.
```