xo-unit: delete obsolete mpl-based implementation #105

	# Workflow to build xo-unit using custom docker container;
	# container provides nix support
	#
	# NOTES
	# 1. GIT_TOKEN granted automatically by github.
	# has read permission on public resources + read/write permission on this repo
	#
	# 2. container built from [[https:github.com:rconybea/docker-nix-builder]]
	# Includes dependencies:
	# - nix
	# - compiler toolchain: gcc, binutils, bash, etc
	# - git
	# - cmake
	# - catch2
	# - pybind11 + python
	# - libwebsockets
	# - jsoncpp
	#
	name: xo-unit nix builder

	on:
	push:
	branches: [ "main" ]
	pull_request:
	branches: [ "main" ]

	env:
	BUILD_TYPE: Release

	jobs:
	build_job:
	name: xo-unit nix build on docker-nix-builder
	runs-on: ubuntu-latest
	container:
	# custom docker image. see github.com:rconybea/docker-nix-builder for definition
	image: ghcr.io/rconybea/docker-nix-builder:v1

	steps:
	# not using usual checkout actions: they don't work out-of-the-box from within a container

	- name: xo-unit
	run: \|
	echo "::group::clone xo-unit repo"
	mkdir -p repo
	GIT_SSL_NO_VERIFY=true git clone https://${{env.GIT_USER}}:${{env.GIT_TOKEN}}@github.com/rconybea/xo-unit.git repo/xo-unit
	echo "::endgroup"

	echo "::group::build xo-unit with nix"
	export NIXPKGS_ALLOW_UNFREE=1
	(cd repo/xo-unit && nix build --impure -L --print-build-logs .#xo-unit && tree ./result)
	echo "::endgroup"

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