Merge pull request #43312 from deads2k/cli-08-discovery

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.
```

api/openapi-spec/swagger.json

@@ -36855,6 +36855,7 @@
     "description": "APIResource specifies the name of a resource and whether it is namespaced.",
     "required": [
      "name",
+     "singularName",
      "namespaced",
      "kind",
      "verbs"
@@ -36865,7 +36866,7 @@
       "type": "string"
      },
      "name": {
-      "description": "name is the name of the resource.",
+      "description": "name is the plural name of the resource.",
       "type": "string"
      },
      "namespaced": {
@@ -36879,6 +36880,10 @@
        "type": "string"
       }
      },
+     "singularName": {
+      "description": "singularName is the singular name of the resource.  This allows clients to handle plural and singular opaquely. The singularName is more correct for reporting status on a single item and both singular and plural are allowed from the kubectl CLI interface.",
+      "type": "string"
+     },
      "verbs": {
       "description": "verbs is a list of supported kube verbs (this includes get, list, watch, create, update, patch, delete, deletecollection, and proxy)",
       "type": "array",