upgrade percy to fix test CI #929

	name: Tests
	on: [push, pull_request]
	jobs:
	test:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@master
	- name: Set up Python 3.7
	uses: actions/setup-python@v1
	with:
	python-version: 3.7
	- name: Set up Node.js
	uses: actions/setup-node@v2
	with:
	node-version: '14'
	- name: Build frontend
	working-directory: ./webiojs
	run: \|
	npm install
	gulp
	cp dist/pywebio.min.* ../pywebio/html/js
	- name: Install Test JS deps
	run: npm install -D @percy/agent
	- name: Install package
	run: pip3 install ".[all]"
	- name: Install dev dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install -r requirements.txt
	- run: npm install --save-dev @percy/cli
	- name: Percy Test
	run: npx percy exec -- bash ./run_all.sh
	working-directory: ./test
	env:
	PERCY_TOKEN: ${{ secrets.PERCY_TOKEN }}
	- name: Upload test output
	uses: actions/upload-artifact@v1
	if: failure()
	with:
	name: test output
	path: test/output
	- name: Upload test output
	uses: codecov/codecov-action@v3
	with:
	working-directory: ./test
	verbose: true # optional (default = false)

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