debugger: avoid non-ASCII char in code file

Avoid non-ASCII char in lib code as a single non-ASCII char forces all
the chars to be stored inefficiently, bloating the binary size. This
also brings the file closer to compatibility with our lint rules.

PR-URL: https://github.com/nodejs/node/pull/38529


Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>