Replace sys.exit() with click.Context.fail()

Use click methods which gives a better output result, and for consistency and potentially using an other interface.

• fail()
• abort()
• exit()
• close()

Write function in tools.py:

from rich_click import click

def fail(message: str) -> None:
    click.get_current_context().fail(message)

The context has to be defined in the function otherwise it does not work.