Show full exception error message when hovering over inline exception name

[Almenon]

dependency on https://github.com/Almenon/AREPL-vscode/issues/324

I tested it with below and it worked!

        return {
            range,
            hoverMessage: `Traceback (most recent call last):
  line 2, in <module>
ValueError: foo`,
            renderOptions: {
                after: {
                    contentText: text
                }
            }
        }