Update widget.py: fix html icon display none #136

	name: Build extension

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

	jobs:
	build:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v2
	- name: Install node
	uses: actions/setup-node@v1
	with:
	node-version: '16.x'
	- name: Install Python
	uses: actions/setup-python@v2
	with:
	python-version: '3.7'
	architecture: 'x64'


	- name: Setup pip cache
	uses: actions/cache@v2
	with:
	path: ~/.cache/pip
	key: pip-3.7-${{ hashFiles('package.json') }}
	restore-keys: \|
	pip-3.7-
	pip-

	- name: Get yarn cache directory path
	id: yarn-cache-dir-path
	run: echo "::set-output name=dir::$(yarn cache dir)"
	- name: Setup yarn cache
	uses: actions/cache@v2
	id: yarn-cache # use this to check for `cache-hit` (`steps.yarn-cache.outputs.cache-hit != 'true'`)
	with:
	path: ${{ steps.yarn-cache-dir-path.outputs.dir }}
	key: yarn-${{ hashFiles('**/yarn.lock') }}
	restore-keys: \|
	yarn-

	- name: Install dependencies
	run: python -m pip install -U jupyterlab~=3.0 jupyter_packaging~=0.7.9 jupyterlab_widgets~=1.0.0
	- name: Build the extension
	working-directory: js
	run: \|
	jlpm
	jlpm run eslint:check
	python -m pip install .

	jupyter labextension list 2>&1 \| grep -ie "nglview-js-widgets.*OK"
	python -m jupyterlab.browser_check

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