Add CI; fix Dialyzer errors; adopt tests for rebar3 #5

	name: CI
	on:
	push:
	branches:
	- master
	pull_request:
	branches:
	- master
	jobs:
	ci:
	name: Run checks and tests over ${{matrix.otp}} and ${{matrix.os}}
	runs-on: ${{matrix.os}}

	strategy:
	fail-fast: false
	matrix:
	otp: ["26.0", "25.3", "24.3"]
	os: ["ubuntu-22.04"]
	include:
	- otp: "23.3"
	os: "ubuntu-20.04"

	steps:
	- uses: actions/checkout@v3

	- uses: erlef/setup-beam@v1
	with:
	otp-version: ${{matrix.otp}}
	rebar3-version: "3.17.0"

	- name: Install gettext
	run: sudo apt-get install -y gettext

	- name: Compile
	run: rebar3 compile

	- name: xref
	run: rebar3 xref

	- name: Eunit test
	run: rebar3 eunit

	- name: Generate docs
	run: rebar3 edoc

	- name: Dialyze
	run: rebar3 dialyzer

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