MAVLinkLogManager: use https as default upload url

src/Vehicle/MAVLinkLogManager.cc

@@ -28,7 +28,7 @@ static const char* kEmailAddressKey         = "Email";
 static const char* kDescriptionsKey         = "Description";
 static const char* kDefaultDescr            = "QGroundControl Session";
 static const char* kPx4URLKey               = "LogURL";
-static const char* kDefaultPx4URL           = "http://logs.px4.io/upload";
+static const char* kDefaultPx4URL           = "https://logs.px4.io/upload";
 static const char* kEnableAutoUploadKey     = "EnableAutoUpload";
 static const char* kEnableAutoStartKey      = "EnableAutoStart";
 static const char* kEnableDeletetKey        = "EnableDelete";