Make connector become virtual-thread friendly

Since java now permits virtual threads, Connector is mostly compatible with those, but there is a few places where connector with synchronize use that will prevent virtual thread to be use with maximum speed.

Like java did internally with BufferedInputStream, BufferedOutputStream, BufferedReader, BufferedWriter, PrintStream, and PrintWriter modified to use an explicit lock rather than a monitor when used directly. Driver default implementation ReadAheadBufferedStream must use explicit lock.