Docker support for linux/arm64 arch

[zees-dev]

Issue

There isn't a docker image for linux/arm64 (also the arch for M1 macs) hence arm64 machines cannot run the current docker image(s) natively.

Also, running the linux/amd64 version of the image on a arm64 machine (via QEMU) throws LIBC errors upon execution of the forc CLI:

# > docker run --platform linux/amd64 --rm -it ghcr.io/fuellabs/forc:sha-861ca10 bash
# > root@8dea8e7d9b31:~# ./forc
./forc: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.32' not found (required by ./forc)
./forc: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.34' not found (required by ./forc)
./forc: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.33' not found (required by ./forc)

The CI needs to be updated to support building for both linux/amd64 and linux/arm64 and publishing these to GHCR (ideally under the same tag).