Update build to auto-detect OS #181

	##############################################################################
	# Copyright Christopher Kormanyos 2023 - 2024.
	# Distributed under The Unlicense.

	name: ti84-ref_app
	on:
	push:
	branches:
	- '**'
	pull_request:
	jobs:
	sdcc-build-native:
	runs-on: ubuntu-latest
	defaults:
	run:
	shell: bash
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: '0'
	- name: get-sdcc-toolchain
	run: \|
	mkdir ../sdcc-root
	cd ../sdcc-root
	wget --no-check-certificate https://sourceforge.net/projects/sdcc/files/sdcc-linux-amd64/4.4.0/sdcc-4.4.0-amd64-unknown-linux2.5.tar.bz2
	tar -xjf sdcc-4.4.0-amd64-unknown-linux2.5.tar.bz2
	- name: build-and-verify-refapp
	run: \|
	cd build
	PATH=../../sdcc-root/sdcc-4.4.0/bin:"$PATH"
	sdcc -v
	make all
	echo 'build-and-verify-refapp partial verify result'
	ls -la ../bin/refapp.8xp
	sdcc-build-native-macos:
	runs-on: macos-latest
	defaults:
	run:
	shell: bash
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: '0'
	- name: get-sdcc-toolchain
	run: \|
	brew install sdcc
	- name: build-and-verify-refapp
	run: \|
	cd build
	sdcc -v
	make all
	echo 'build-and-verify-refapp partial verify result'
	ls -la ../bin/refapp.8xp

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