Investigate how to lower the risk of losing the first pasted line into the REPL

[anthonykim1]

For reported Python REPL users with different Operating Systems, there has been instances where the very first command that is sent to REPL is lost. Investigate problem and fix.

[anthonykim1]

This long-standing problem existed with the nature of how commands were being sent to the REPL. Historically, the very first command sent to the Python REPL have shown to be swollen up entirely, or gets pasted twice both in the Terminal and Python REPL. Historically, we gave 'one-second' to send the command.

With the Python REPL created/launched via using Terminal by nature of design, we do not have context of where or not Python REPL successfully launched or not. Now, with using 'onDidWriteTerminalData' from VS Code, we are able to watch whether Python REPL has launched or not by observing Python REPL marker >>> in Terminal.

Also given that we are just launching Python REPL instance, we do not have any context of what is going on with launched Python REPL. Python extension would have much better context and control over what is going on inside REPL with "VS Code Native" REPL to be built in the future.