Add an Option to hide the welcome notice

[L-Wehmschulte]

Feature Description

Hi everyone,
I'd like to propose a small feature flag for this great program:
--hideWelcomeNotice
If this feature flag is set, it will hide the welcome notice shown when starting the REPL:

Welcome to the C# REPL (Read Eval Print Loop)!
Type C# expressions and statements at the prompt and press Enter to evaluate them.
Type help to learn more, exit to quit, and clear to clear your terminal.

The reason why I'd like this to be added is, that in my workflow I use the Windows-Terminal Quake-Window, which has limited vertical space and the Welcome notice takes up a considerable part of that space.

Alternatives:

• My current workflow is to always type clear at the beginning of each session, which is getting a little bothersome

I have already started development of this feature on my own and would like to open a Pull Request once this issue has been reviewed.

Thank you very much for your review and have a nice day!
~ Louis