more usage notes in readme #32

	name: CI

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

	jobs:
	build:
	name: Build and Test OTP ${{matrix.otp}} / Elixir ${{matrix.elixir}}
	runs-on: ubuntu-latest
	strategy:
	matrix:
	otp: [23, 24, 25]
	elixir: [1.14]

	env:
	MIX_ENV: test
	ImageOS: ubuntu20 # equivalent to runs-on ubuntu-20.04

	steps:
	- uses: actions/checkout@v3

	- name: Set up Elixir
	uses: erlef/setup-beam@v1
	with:
	elixir-version: ${{matrix.elixir}} # Define the elixir version [required]
	otp-version: ${{matrix.otp}} # Define the OTP version [required]

	- uses: actions/cache@v1
	id: deps-cache
	with:
	path: deps
	key: ${{ runner.os }}-mix-${{ matrix.otp }}-${{ matrix.elixir }}-${{ hashFiles(format('{0}{1}', github.workspace, '/mix.lock')) }}

	- uses: actions/cache@v1
	id: build-cache
	with:
	path: _build
	key: ${{ runner.os }}-build-${{ matrix.otp }}-${{ matrix.elixir }}-${{ hashFiles(format('{0}{1}', github.workspace, '/mix.lock')) }}

	- name: Install dependencies
	run: mix deps.get

	- name: Run tests
	run: mix test

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