Updated Grease to v1.18.0 #199

	## Adapted from:
	## - Roassal3 - https://github.com/ObjectProfile/Roassal3/blob/36b92db2055501c87f2ccea5573fc83fb4916884/.github/workflows/runTests.yml
	## - Willow-Playground - https://github.com/ba-st/Willow-Playground/blob/2898e1afbdd5a6011721e5a640225f81ae895de2/.github/workflows/build.yml0

	name: CI

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

	# Allows you to run this workflow manually from the Actions tab
	workflow_dispatch:

	# 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:
	# The type of runner that the job will run on
	runs-on: ubuntu-latest

	strategy:
	matrix:
	smalltalk: [ Pharo64-10, Pharo64-9.0, Pharo64-8.0, Pharo64-7.0 ]
	name: ${{ matrix.smalltalk }}

	# 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

	- uses: hpi-swa/setup-smalltalkCI@v1
	with:
	smalltalk-image: ${{ matrix.smalltalk }}
	- name: Load Image and Run Tests
	run: smalltalkci -s ${{ matrix.smalltalk }}
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	timeout-minutes: 15
	# - name: Upload coverage to Codecov
	# uses: codecov/codecov-action@v1
	# with:
	# name: ${{matrix.os}}-${{matrix.smalltalk}}
	# token: ${{ secrets.CODECOV_TOKEN }}

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