Update actions/checkout action to v4 #51

	name: linux_neovim

	on:
	push:
	branches:
	- master
	pull_request:
	branches:
	- master

	jobs:
	build:
	strategy:
	fail-fast: false
	matrix:
	os: [ubuntu-latest]
	name: [neovim-v04-x64,neovim-nightly-x64]
	include:
	- name: neovim-v04-x64
	os: ubuntu-latest
	neovim_version: v0.4.3
	- name: neovim-nightly-x64
	os: ubuntu-latest
	neovim_version: nightly
	runs-on: ${{matrix.os}}
	steps:
	- uses: actions/checkout@v4
	- name: Download neovim
	shell: bash
	run: \|
	mkdir -p ~/nvim/bin
	curl -L https://github.com/neovim/neovim/releases/download/${{matrix.neovim_version}}/nvim.appimage -o ~/nvim/bin/nvim
	chmod u+x ~/nvim/bin/nvim
	- name: Download test runner
	shell: bash
	run: git clone --depth 1 --branch v1.5.4 --single-branch https://github.com/thinca/vim-themis ~/themis
	- name: Run tests
	shell: bash
	run: \|
	export PATH=~/nvim/bin:$PATH
	export PATH=~/themis/bin:$PATH
	export THEMIS_VIM=nvim
	nvim --version
	themis --reporter spec

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