feat(build): create debug symbols package

[locao]

Summary

To keep the size impact of adding Wasm to the Gateway images to a minimum, we are splitting the debug symbols out of ngx_wasm_module.so into an independent file (ngx_wasm_module.so.dbg) and packaging it in a new package, kong-debuginfo.

As the new package is called kong-debuginfo, libatc_router.so was also splitted into a new debug shared object, keeping the behavior consistent in all kong-owned shared objects.

Checklist

• The Pull Request has tests
• A changelog file has been added to CHANGELOG/unreleased/kong or adding skip-changelog label on PR if unnecessary. README.md (Please ping @vm-001 if you need help)
• There is a user-facing docs PR against https://github.com/Kong/docs.konghq.com - PUT DOCS PR HERE

Full changelog

• New build argument to split shared objects.
• Build step to split kong shared objects.
• New package containing only the debug shared objects.

Issue reference

KAG-1990

[fffonion]

I'm generally onboard to put all debug symbols in seperate package (see https://konghq.atlassian.net/browse/KAG-994), but I'm not sure how other people feel about it.
So it feels bit intermediate state to me that we are also splitting atc_router.so. My suggestion is to either only keep doing for wasm libraries, or do for all other libraries.
Let's also use well-known naming conversion for debug info packages, like kong.debugsyms.ddeb.

[github-actions]

This PR is marked as stale because it has been open for 14 days with no activity.

[locao]

I am closing this PR for the time being. It seems we don't want to include this change any time soon.