fix MIME subtype for html mail #171

	# .github/workflows/unittest.yml: configuration file for github actions worflow
	# This file was automatically generated using 'python -m vsc.install.ci'
	# DO NOT EDIT MANUALLY
	jobs:
	python_unittests:
	runs-on: ubuntu-20.04
	steps:
	- name: Checkout code
	uses: actions/checkout@v3
	- name: Setup Python
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python }}
	- name: install tox
	run: pip install 'virtualenv<20.22.0' 'tox<4.5.0'
	- name: add mandatory git remote
	run: git remote add hpcugent https://github.com/hpcugent/vsc-base.git
	- name: Run tox
	run: tox -e py
	strategy:
	matrix:
	python:
	- 3.6
	- 3.9
	name: run python tests
	'on':
	- push
	- pull_request

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