Bump tornado from 6.4.1 to 6.4.2 in /docs #237

	name: C++ build with CMake
	permissions: read-all

	# Controls when the action will run:
	# Triggers the workflow on push or pull request events but only for the master branch
	on:
	push:
	branches: [ master ]
	pull_request:
	branches: [ master, development ]

	# A workflow run is made up of one or more jobs that can run sequentially or in parallel
	jobs:
	# This workflow contains a single job called "build"
	build-ubuntu-gcc:
	# The type of runner that the job will run on
	runs-on: ubuntu-latest

	# Steps represent a sequence of tasks that will be executed as part of the job
	steps:
	# Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
	- uses: actions/checkout@v2

	- name: configure
	run: mkdir build && cd build && CXX=g++ cmake -DIqsMPI=OFF -DIqsUtest=ON ..
	- name: build
	run: cmake --build build

	- name: unit test
	run: ./build/bin/utest

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