Remove old workflows, add a build workflow #3

	name: Test built-in extensions build/packaging
	on:
	pull_request:
	branches:
	- master
	env:
	NODE_OPTIONS: --max-old-space-size=8192
	jobs:
	linux:
	runs-on: ubuntu-latest
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	steps:
	- uses: actions/checkout@v1
	- run: \|
	git submodule init
	git submodule update
	name: Checkout VS Code
	# should be aligned with https://github.com/microsoft/vscode/blob/8031c495a65de120560d27703c415eb44c3a99a1/.github/workflows/ci.yml#L22-L32
	- run: \|
	sudo apt-get update
	sudo apt-get install -y libxkbfile-dev pkg-config libsecret-1-dev libxss1 dbus xvfb libgtk-3-0
	sudo cp vscode/build/azure-pipelines/linux/xvfb.init /etc/init.d/xvfb
	sudo chmod +x /etc/init.d/xvfb
	sudo update-rc.d xvfb defaults
	sudo service xvfb start
	name: Setup Build Environment
	- uses: actions/setup-node@v1
	with:
	node-version: 18
	- run: npx ovsx --version
	name: Check ovsx version
	- run: \|
	yarn
	yarn build:extensions
	name: Bundle Extensions
	- run: yarn package-vsix:latest
	name: Package Solid Version of Extensions
	- run: yarn create-extension-pack:latest
	name: Create built-in extensions pack

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