Add PySide QtPdf for plugin use #570

	name: Build Sigil on Linux

	on:
	push:
	branches: [ master ]
	tags-ignore:
	- '**'
	paths-ignore:
	- 'docs/**'
	- 'installer/win_installer_note.txt'
	- 'ChangeLog.txt'
	- 'COPYING.txt'
	- 'version.xml'
	- 'appveyor.yml'
	- '.retired_travis.yml'
	- '**.md'
	- '/reset--caches.txt'

	pull_request:
	branches: [ master ]
	tags-ignore:
	- '**'
	paths-ignore:
	- 'docs/**'
	- 'installer/win_installer_note.txt'
	- 'ChangeLog.txt'
	- 'COPYING.txt'
	- 'version.xml'
	- 'appveyor.yml'
	- '.retired_travis.yml'
	- '**.md'
	- '/reset--caches.txt'

	env:
	BUILD_TYPE: Debug

	jobs:
	build:
	if: "!contains(github.event.head_commit.message, '[skip ci]')"
	runs-on: ubuntu-20.04

	steps:
	- uses: actions/checkout@v2

	- uses: actions/setup-python@v2
	with:
	python-version: '3.6'

	- name: Cache Qt
	id: cache-qt
	uses: actions/cache@v2
	with:
	path: ${{runner.workspace}}/Qt
	key: ${{ runner.os }}-sigilqt-${{ hashFiles('**/reset-lin-caches.txt') }}

	- name: Install Qt
	uses: jurplel/install-qt-action@v2
	with:
	version: '5.10.0'
	dir: ${{runner.workspace}}/Qt
	modules: 'qtwebengine'
	setup-python: 'false'
	cached: ${{ steps.cache-qt.outputs.cache-hit }}

	- uses: lukka/get-cmake@latest

	- name: Install dependencies
	run: \|
	sudo apt install mesa-common-dev libglu1-mesa-dev
	mkdir ${{runner.workspace}}/build
	cmake --version
	ninja --version
	qmake -v
	python3 --version
	gcc --version

	- name: Build Sigil
	working-directory: ${{runner.workspace}}/build
	run: \|
	cmake $GITHUB_WORKSPACE \
	-G "Ninja" \
	-DCMAKE_BUILD_TYPE=$BUILD_TYPE \
	-DUSE_SYSTEM_LIBS=1 \
	-DSYSTEM_LIBS_REQUIRED=0
	ninja -j$(getconf _NPROCESSORS_ONLN)

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