Update e2e test to reproduce bug reported in #462 #1054

	name: python coverage

	on:
	push:
	branches:
	- master
	pull_request: {}

	jobs:
	coverage:
	runs-on: ubuntu-latest

	# Not intended for forks.
	if: github.repository == 'optuna/optuna-dashboard'

	steps:
	- name: Checkout
	uses: actions/checkout@v4

	- name: Setup Python
	uses: actions/setup-python@v4
	with:
	python-version: '3.10'
	architecture: x64

	- name: Install dependencies
	run: \|
	python -m pip install --progress-bar off --upgrade pip setuptools
	pip install --progress-bar off .[optional]
	pip install --progress-bar off .[test]
	pip install --progress-bar off .
	echo 'import coverage; coverage.process_startup()' > sitecustomize.py
	- name: Tests
	env:
	PYTHONPATH: . # To invoke sitecutomize.py
	COVERAGE_PROCESS_START: .coveragerc # https://coverage.readthedocs.io/en/6.4.1/subprocess.html
	COVERAGE_COVERAGE: yes # https://github.com/nedbat/coveragepy/blob/65bf33fc03209ffb01bbbc0d900017614645ee7a/coverage/control.py#L255-L261
	run: \|
	coverage run --source=optuna_dashboard -m pytest python_tests
	coverage combine
	coverage xml
	- name: Upload coverage to Codecov
	uses: codecov/codecov-action@v3
	with:
	token: ${{ secrets.CODECOV_TOKEN }}
	file: ./coverage.xml
	fail_ci_if_error: false

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