Several fixes #65

	##############################################################################
	# GitHub Actions Workflow to test the R interface of volesti
	#
	# Copyright (c) 2020 Vissarion Fisikopoulos
	#
	# Licensed under GNU LGPL.3, see LICENCE file
	##############################################################################

	on: [push, pull_request]

	name: R-CMD-check-ubuntu

	jobs:
	R-CMD-check:
	runs-on: ${{ matrix.config.os }}

	name: ${{ matrix.config.os }} (${{ matrix.config.r }})

	strategy:
	fail-fast: false
	matrix:
	config:
	- {os: ubuntu-latest, r: 'devel'}
	- {os: ubuntu-latest, r: 'release'}

	env:
	R_REMOTES_NO_ERRORS_FROM_WARNINGS: true
	RSPM: ${{ matrix.config.rspm }}
	GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}

	steps:
	- uses: actions/checkout@v3
	- run: sudo apt-get update \|\| true;
	sudo apt install build-essential libcurl4-gnutls-dev libxml2-dev libssl-dev libgit2-dev libfontconfig1-dev libharfbuzz-dev libfribidi-dev;

	- uses: r-lib/actions/setup-r@v2
	with:
	r-version: ${{ matrix.config.r }}

	- uses: r-lib/actions/setup-pandoc@v2

	- name: Install dependencies
	run: Rscript -e "install.packages(c('testthat', 'pkgload', 'rcmdcheck', 'devtools', 'Rcpp', 'RcppEigen', 'BH', 'downloader', 'xfun', dependencies=TRUE))";

	- name: Check
	env:
	_R_CHECK_CRAN_INCOMING_REMOTE_: false
	run: Rscript -e "library(rcmdcheck)" -e "rcmdcheck::rcmdcheck(args = c('--no-manual'), error_on = 'warning', check_dir = 'check')"

	- name: Upload check results
	if: failure()
	uses: actions/upload-artifact@v2
	with:
	name: ${{ runner.os }}-r${{ matrix.config.r }}-results
	path: check

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