tests: Refactors PodSandbox creation

Most of the tests creating and using Pod Sandboxes in the same way. We can create
a common function that will do that for us, so we can have less duplicated code,
and make it easier to add new tests in the future.

Signed-off-by: Claudiu Belu <cbelu@cloudbasesolutions.com>

integration/container_stop_test.go

@@ -76,13 +76,7 @@ func TestContainerStopCancellation(t *testing.T) {
 		t.Skip("Skipped on Windows.")
 	}
 	t.Log("Create a pod sandbox")
-	sbConfig := PodSandboxConfig("sandbox", "cancel-container-stop")
-	sb, err := runtimeService.RunPodSandbox(sbConfig, *runtimeHandler)
-	require.NoError(t, err)
-	defer func() {
-		assert.NoError(t, runtimeService.StopPodSandbox(sb))
-		assert.NoError(t, runtimeService.RemovePodSandbox(sb))
-	}()
+	sb, sbConfig := PodSandboxConfigWithCleanup(t, "sandbox", "cancel-container-stop")
 
 	var (
 		testImage     = GetImage(BusyBox)