Update CircleCI workflow, setting environment var. #125

	on:
	push:
	branches:
	- main
	pull_request:
	branches:
	- main
	workflow_dispatch:
	# enable manual triggering
	schedule:
	# run testing on the first of each month 5am ET / 9am UTC
	- cron: '0 9 1 * *'

	jobs:
	R-build:
	strategy:
	fail-fast: false
	matrix:
	R: [ '4.3.1', '4.4.1' ]
	os: [ 'macos-15-intel', 'ubuntu-latest', 'windows-latest']
	exclude:
	- R: '4.3.1'
	os: 'windows-latest'
	runs-on: ${{ matrix.os }}
	name: ${{ matrix.R }} ${{ matrix.os }} build
	env:
	R_LIBS: ${{ github.workspace }}/Rlibs

	steps:
	- uses: actions/checkout@v6
	with:
	fetch-depth: 0
	ref: ${{ github.event.pull_request.head.sha }}
	- name: Setup R
	uses: r-lib/actions/setup-r@v2
	with:
	r-version: ${{ matrix.R }}
	- name: System Dependencies
	if: startsWith( matrix.os, 'ubuntu' )
	run: \|
	sudo apt-get -y update &&
	sudo apt-get install -y libcurl4-openssl-dev libssh2-1-dev libharfbuzz-dev libfribidi-dev gh &&
	sudo rm -rf /var/lib/apt/lists/*
	- name: Configuration Information
	shell: bash
	run: \|
	mkdir -p "$R_LIBS"
	cmake --version
	if [[ "$RUNNER_OS" == "Windows" ]]; then
	g++ --version
	else
	c++ --version
	fi
	which R
	R --version
	- name: Install R packages
	shell: bash
	run: \|
	R -e "install.packages(c('remotes'), lib=Sys.getenv('R_LIBS'), repos='https://cloud.r-project.org/')"
	- name: Build and test
	shell: bash
	env:
	ITK_GLOBAL_DEFAULT_NUMBER_OF_THREADS: 2
	run: \|
	R -e "Sys.setenv(MAKEJ=2); remotes::install_git(c('.'), lib=Sys.getenv('R_LIBS'))"

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