Merge pull request #41151 from ahakanbaba/tpr-unit-tests

Automatic merge from submit-queue (batch tested with PRs 41937, 41151, 42092, 40269, 42135)

Add a unit test for idempotent applys to the TPR entries.

The test in apply_test follows the general pattern of other tests.
We load from a file in test/fixtures and mock the API server in the
function closure in the HttpClient call.
The apply operation expects a last-modified-configuration annotation.
That is written verbatim in the test/fixture file.

References #40841



**What this PR does / why we need it**:
Adds one unit test for TPR's using applies. 

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
References: 
https://github.com/kubernetes/features/issues/95
https://github.com/kubernetes/kubernetes/issues/40841#issue-204769102


**Special notes for your reviewer**:

I am not super proud of the tpr-entry name. 
But I feel like we need to call the two objects differently. 
The one which has Kind:ThirdPartyResource 
and the one has Kind:Foo. 

Is the name "ThirdPartyResource" used interchangeably for both ? I used tpr-entry for the Kind:Foo object.

Also I !assume! this is testing an idempotent apply because the last-applied-configuration annotation is the same as the object itself. 

This is the state I see in the logs of kubectl if I do a proper idempotent apply of a third party resource entry. 

I guess I will know more once I start playing around with apply command that change TPR objects. 

**Release note**:

```release-note
```

pkg/kubectl/cmd/testing/fake.go

@@ -761,5 +761,21 @@ func testDynamicResources() []*discovery.APIGroupResources {
 				},
 			},
 		},
+		{
+			Group: metav1.APIGroup{
+				Name: "unit-test.test.com",
+				Versions: []metav1.GroupVersionForDiscovery{
+					{GroupVersion: "unit-test.test.com/v1", Version: "v1"},
+				},
+				PreferredVersion: metav1.GroupVersionForDiscovery{
+					GroupVersion: "unit-test.test.com/v1",
+					Version:      "v1"},
+			},
+			VersionedResources: map[string][]metav1.APIResource{
+				"v1": {
+					{Name: "widgets", Namespaced: true, Kind: "Widget"},
+				},
+			},
+		},
 	}
 }