It’s not fully in use for building Kong releases (there’s a PR to have it do the daily builds) but I’d still consider it authoritative / good prior art on how to build Kong from source. The openssl specific part within that repository is here https://github.com/Kong/kong-build-tools/blob/master/Dockerfile.openresty#L13-L14
Hopefully the repository README / Makefile greatly simplifies building Kong from source feel free to take it for a spin and ping me any questions / challenges.
Kong does not make use of the OpenResty directives that require these OpenSSL patches. As such, you do not need to apply these patches when installing Kong from source.