Fix bug when to_gis() is called on a network with a leak #642

	# This workflow will install Python dependencies, run tests and lint with a single version of Python
	# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions

	name: quick-check

	on:
	push:
	branches:
	- '**'
	pull_request:
	branches:
	- '**'

	jobs:
	test:
	strategy:
	matrix:
	python-version: ['3.9', '3.11']
	fail-fast: false
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install packages
	run: \|
	python -m pip install --upgrade pip
	pip install -r requirements.txt
	pip install --upgrade coverage pytest
	- name: Install package for development
	run: \|
	python -m pip install -e .
	- name: Run tests and coverage (unittests plus doctests)
	run: \|
	coverage run --source=wntr --omit="/tests/","/sim/network_isolation/network_isolation.py","/sim/aml/evaluator.py" -m pytest -m "not time_consuming" --doctest-modules --doctest-glob="*.rst" wntr
	coverage run --source=wntr --omit="/tests/","/sim/network_isolation/network_isolation.py","/sim/aml/evaluator.py" --append -m pytest --doctest-glob="*.rst" documentation
	coverage report --fail-under=70
	# coverage run --source=wntr --omit="/tests/" --append -m pytest --doctest-glob="*.rst" documentation

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