ci.yml: add beta version, split experimental versions #819

	name: ci
	on:
	- push
	- pull_request
	jobs:
	test:
	name: Julia ${{ matrix.version }} - ${{ matrix.os }} - ${{ matrix.arch }}
	continue-on-error: ${{ matrix.experimental }}
	runs-on: ${{ matrix.os }}
	strategy:
	fail-fast: false
	matrix:
	version:
	- '1.6'
	- '1'
	os:
	- ubuntu-latest
	- macOS-latest
	- windows-latest
	arch:
	- x64
	experimental:
	- false
	include:
	- version: 'beta'
	os: ubuntu-latest
	arch: x64
	experimental: true
	- version: 'beta'
	os: macOS-latest
	arch: x64
	experimental: true
	- version: 'beta'
	os: windows-latest
	arch: x64
	experimental: true
	- version: 'nightly'
	os: ubuntu-latest
	arch: x64
	experimental: true
	- version: 'nightly'
	os: macOS-latest
	arch: x64
	experimental: true
	- version: 'nightly'
	os: windows-latest
	arch: x64
	experimental: true
	steps:
	- uses: actions/checkout@v2
	- uses: julia-actions/setup-julia@latest
	with:
	version: ${{ matrix.version }}
	arch: ${{ matrix.arch }}
	- uses: julia-actions/julia-buildpkg@latest
	- uses: julia-actions/julia-runtest@latest
	build:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: julia-actions/setup-julia@latest
	with:
	version: '1'
	- name: Install dependencies
	run: julia --project=docs/ -e 'using Pkg; Pkg.develop(PackageSpec(path=pwd())); Pkg.instantiate()'
	- name: Build and deploy
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }} # For authentication with GitHub Actions token
	run: julia --project=docs/ docs/make.jl

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