integration: Adds Windows equivalent for TestSandboxRemoveWithoutIPLeakage

Adds an equivalent TestSandboxRemoveWithoutIPLeakage for Windows, in which
we assert that the IPs are not leaked when a Pod's HNS namespace dissapears
and the Pod is deleted afterwards.

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

integration/main_test.go

@@ -377,8 +377,12 @@ func KillProcess(name string) error {
 }
 
 // KillPid kills the process by pid. kill is used.
-func KillPid(pid int) error { //nolint:unused
-	output, err := exec.Command("kill", strconv.Itoa(pid)).CombinedOutput()
+func KillPid(pid int) error {
+	command := "kill"
+	if goruntime.GOOS == "windows" {
+		command = "tskill"
+	}
+	output, err := exec.Command(command, strconv.Itoa(pid)).CombinedOutput()
 	if err != nil {
 		return errors.Errorf("failed to kill %d - error: %v, output: %q", pid, err, output)
 	}