Disable process warnings per Environment variable

[Uzlopak]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the feature has not already been requested

🚀 Feature Proposal

It should be possible to disable warnings per environment variable, e.g. PROCESS_WARNING_DISABLE=1, or maybe specify which warnings to disable, e.g. PROCESS_WARNING_DISABLE=FSTDEP018,FSTDEP015

Motivation

It could be useful to disable process warnings, especially now that we are deprecating more and more functionality in fastify v4.

If we would decide to allow specifying which warnings should not be emitted anymore, then a dev could be empowered to "acknowledge" the warning and realize that there is a potential technical debt, but maybe does not want to solve the warning immediatly.

Example

No response

[jsumners]

Use https://nodejs.org/dist/latest-v18.x/docs/api/cli.html#--no-warnings

[Uzlopak]

We should check if our warnings get also suppressed and if so document it in readme.md.

[Uzlopak]

@jsumners

Allrighty. Investigated this. Added docs in #83 + tests to ensure it really works ;).