report: remove verbose setting

This commit removes the --diagnostic-report-verbose CLI option
and all associated logic. The flag is currently only used in one
place, and only reflects the settings at startup. Additionally,
Node tends to use the NODE_DEBUG mechanism for adding verbose
output.

PR-URL: https://github.com/nodejs/node/pull/26195


Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>