Python REPL should omit empty output

[rebornix]

Testing #23484

In Jupyter Interactive Window, ipykernel doesn't generate output for a variable assignment

However with Python REPL, it always generate an empty output

[anthonykim1]

Mentioned here: #23698 also but will work to resolve this

[anthonykim1]

Verification step:

1. Install latest pre-release version of Python extension
2. Enable setting to send to native REPL
3. shift+enter in Python file to trigger opening of native REPL
4. type in code that won't produce output such as import code
5. Observe you do not get a single line of output.