[WIP] create a problem to study impact of species composition gradient on shock burning in 1D #1669

	name: exact Riemann

	on: [pull_request]
	jobs:
	exact_riemann:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- name: Get submodules
	run: \|
	git submodule update --init
	cd external/Microphysics
	git fetch; git checkout development
	cd ../amrex
	git fetch; git checkout development
	cd ../..

	- name: Install dependencies
	run: \|
	sudo apt-get update -y -qq
	sudo apt-get -qq -y install curl cmake jq clang g++>=9.3.0

	- name: Compile exact_riemann
	run: \|
	cd Util/exact_riemann
	make -j 4

	- name: Run test1
	run: \|
	cd Util/exact_riemann
	./Castro3d.gnu.ex inputs.test1.helm

	- name: Compare to stored output
	run: \|
	cd Util/exact_riemann
	diff riemann.out ci-benchmarks/test1-riemann.out

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