Adds nexus version file #5

	name: nexus version check

	on:
	push:
	branches: [master]
	pull_request:
	branches: [master]

	jobs:
	linting:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: Set up Python 3.10
	uses: actions/setup-python@v2
	with:
	python-version: "3.10"
	- name: Generate nexus git version
	run: \|
	git submodule sync --recursive
	git submodule update --init --recursive --jobs=4
	git submodule foreach --recursive 'git fetch --tags'
	cd pynxtools/definitions
	git describe --dirty --tags --long --match "[0-9]" > ../nexus-ref.txt
	cd ../
	- uses: GuillaumeFalourd/diff-action@v1
	with:
	first_file_path: pynxtools/nexus-version.txt
	second_file_path: pynxtools/nexus-ref.txt
	expected_result: PASSED

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