fix build runner version : ubuntu 18 is no longer supported. #245

	# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
	# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions

	name: kapture-main

	on:
	push:
	branches: [ main ]
	pull_request:
	branches: [ main ]

	jobs:
	build:

	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: [3.6, 3.8]

	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}
	- name: Cache pip
	uses: actions/cache@v2
	with:
	# This path is specific to Ubuntu
	path: ~/.cache/pip
	# Look to see if there is a cache hit for the corresponding requirements file
	key: ${{ runner.os }}-pip-${{ hashFiles('requirements.txt') }}
	restore-keys: \|
	${{ runner.os }}-pip-
	${{ runner.os }}-
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install flake8 pytest
	if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
	- name: Lint with flake8
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
	# exit-zero treats all errors as warnings. We allow 120 chars wide lines
	flake8 . --count --exit-zero --max-complexity=16 --max-line-length=120 --statistics --extend-ignore=F401
	- name: Test with unittest
	run: \|
	python -m unittest discover -s tests/

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