Migrate to Selenium 4, add Scala 3 #23

	name: CI
	on:
	push:
	branches:
	- main
	pull_request:
	branches:
	- main
	jobs:
	build:
	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	scalaversion: ["2.12.20", "2.13.15"]
	browser: ["chrome"]
	include:
	- scalaversion: "2.12.20"
	browser: "firefox"
	env:
	SJS_TEST_BROWSER: ${{ matrix.browser }}
	steps:
	- uses: actions/checkout@v2
	- uses: olafurpg/setup-scala@v10
	with:
	java-version: "adopt@1.11"
	- uses: coursier/cache-action@v5
	- name: Scalastyle
	run: >
	sbt "++${{ matrix.scalaversion }}"
	seleniumJSEnv/scalastyle
	seleniumJSEnv/Test/scalastyle
	seleniumJSEnvTest/scalastyle
	seleniumJSHttpEnvTest/Test/scalastyle
	seleniumJSEnvTest/Test/scalastyle
	- name: MiMa
	run: sbt "++${{ matrix.scalaversion }}" seleniumJSEnv/mimaReportBinaryIssues
	- name: Unit tests
	run: sbt "++${{ matrix.scalaversion }}" seleniumJSEnv/test
	- name: Integration tests
	run: >
	sbt "++${{ matrix.scalaversion }}"
	seleniumJSEnvTest/test
	'set scalaJSStage in Global := FullOptStage'
	seleniumJSEnvTest/test
	- name: Start HTTP server
	run: "python3 -m http.server 8080 &"
	- name: Integration tests with HTTP server
	run: >
	sbt "++${{ matrix.scalaversion }}"
	seleniumJSHttpEnvTest/test
	'set scalaJSStage in Global := FullOptStage'
	seleniumJSHttpEnvTest/test

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