feat: add multi-arch Dockerfiles and scripts

[vpavlin]

Description

Adding Dockerfiles and Makefile targets to build static binaries for amd64 and arm64, produce archives with those binaries and build minimal docker images.

It uses pre-built container images to ensure stable build environment - DFs and build script are located in ./docker/base/

To build the binary it mounts current working directory (nwaku repo) and then remounts vendor and build with architecture specific folders to avoid conflicts (e.g. when building arm64, dependencies will be cloned into vendor-arm64 and result will be located in build/arm64/)

EDIT: There are targets for packing up the binaries (make dist-$(ARCH)) and building final container images (make dist-container-$(ARCH))

I've also added an experimental make release-notes which uses sv4git to generate changelog/release notes based on semantic commit messages

Missing

• Final container images naming
• Final registry/repository for builder images
• MacOS build

Changes

No changes to existing code, only additions for now

How to test

If you want to run everything, you can execute

make -j$(nproc) dist-container

It will

1. build static binaries for both amd64 and arm64
2. create artifact tarballs in dist/ folder
3. build arm64 and amd64 container images with the static binaries

Keep in mind that compiling for arm64 on non-arm hardware takes significantly longer than building amd64 on amd64