metrics/librato: ensure resp.body closed (#26969)

This change ensures that we call Close on a http response body, in various places in the source code (mostly tests)

p2p/simulations/adapters/exec.go

@@ -428,9 +428,11 @@ func execP2PNode() {
 
 	// Send status to the host.
 	statusJSON, _ := json.Marshal(status)
-	if _, err := http.Post(statusURL, "application/json", bytes.NewReader(statusJSON)); err != nil {
+	resp, err := http.Post(statusURL, "application/json", bytes.NewReader(statusJSON))
+	if err != nil {
 		log.Crit("Can't post startup info", "url", statusURL, "err", err)
 	}
+	resp.Body.Close()
 	if stackErr != nil {
 		os.Exit(1)
 	}

p2p/simulations/mocker_test.go

@@ -124,6 +124,7 @@ func TestMocker(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Could not start mocker: %s", err)
 	}
+	resp.Body.Close()
 	if resp.StatusCode != 200 {
 		t.Fatalf("Invalid Status Code received for starting mocker, expected 200, got %d", resp.StatusCode)
 	}
@@ -145,15 +146,17 @@ func TestMocker(t *testing.T) {
 	if err != nil {
 		t.Fatalf("Could not stop mocker: %s", err)
 	}
+	resp.Body.Close()
 	if resp.StatusCode != 200 {
 		t.Fatalf("Invalid Status Code received for stopping mocker, expected 200, got %d", resp.StatusCode)
 	}
 
 	//reset the network
-	_, err = http.Post(s.URL+"/reset", "", nil)
+	resp, err = http.Post(s.URL+"/reset", "", nil)
 	if err != nil {
 		t.Fatalf("Could not reset network: %s", err)
 	}
+	resp.Body.Close()
 
 	//now the number of nodes in the network should be zero
 	nodesInfo, err = client.GetNodes()