(core) small bugfix in fix #64

	name: Linux

	on:
	push:
	paths:
	- 'pysipfenn/**'
	- '.github/workflows/coreTests_LinuxUbuntu.yaml'
	workflow_dispatch:

	jobs:
	coreTest:
	strategy:
	matrix:
	python-version: ["3.9", "3.10", "3.11"]
	fail-fast: false
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4

	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python-version }}
	cache: 'pip'
	cache-dependency-path: 'pyproject.toml'

	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	python -m pip install --upgrade setuptools
	python -m pip install wheel flask pytest
	python -m pip install -e .
	- name: Test with pytest
	run: \|
	pytest --durations=0

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