Keep log level consistency.

[hwc0919]

No description provided.

[hwc0919]

Other places use LOG_DEBUG.
It causes some false alarms in my application, so I want to make a change.

trantor/trantor/net/inner/TcpConnectionImpl.cc

Lines 881 to 891 in 79e1ffc

	auto thisPtr = weakPtr.lock();
	if (!thisPtr)
	{
	LOG_DEBUG << "Connection is closed,give up sending";
	return false;
	}
	if (thisPtr->status_ != ConnStatus::Connected)
	{
	LOG_DEBUG << "Connection is not connected,give up sending";
	return false;
	}