test: check and handle error for testing

internal/transport/https_test.go

@@ -46,7 +46,8 @@ func TestHTTPSServer_Listen(t *testing.T) {
 		return
 	}
 	assert.NotNil(t, listener)
-	listener.Close()
+	err = listener.Close()
+	assert.NoError(t, err)
 }
 
 func TestHTTPSServer_Serve(t *testing.T) {
@@ -62,7 +63,8 @@ func TestHTTPSServer_Serve(t *testing.T) {
 
 	go func() {
 		time.Sleep(100 * time.Millisecond)
-		listener.Close()
+		err = listener.Close()
+		assert.NoError(t, err)
 	}()
 
 	err = srv.Serve(listener)
@@ -111,6 +113,8 @@ func TestHTTPSServer_Serve_Success(t *testing.T) {
 	_, _ = conn.Write([]byte("GET / HTTP/1.1\r\nHost: ping.example.com\r\n\r\n"))
 
 	time.Sleep(100 * time.Millisecond)
-	conn.Close()
-	listener.Close()
+	err = conn.Close()
+	assert.NoError(t, err)
+	err = listener.Close()
+	assert.NoError(t, err)
 }