build: add --error-on-warn configure flag

This commit adds a configuration time flag named error-on-warn:
$ ./configure --help | grep -A1 error-on-warn
  --error-on-warn       Turn compiler warnings into errors for node core
                        sources.

The motivation for this is that CI jobs can use this flag to turn
warnings into errors.

PR-URL: https://github.com/nodejs/node/pull/32685


Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Matheus Marchini <mat@mmarchini.me>