Update CI to checkout@v4, setup-dotnet@v4 #61

	name: CI
	on: [push, pull_request]
	jobs:
	build-test:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	- name: Setup .NET Core
	uses: actions/setup-dotnet@v4
	with:
	dotnet-version: 6.0.x
	- name: Restore packages
	run: dotnet restore
	- name: Build
	run: dotnet build --configuration Release --no-restore
	- name: Test
	run: dotnet test --no-restore --verbosity normal
	build-image:
	name: Build & Push (Docker)
	needs: build-test
	runs-on: ubuntu-latest
	env:
	dockerId: ${{ secrets.dockerid }}
	dockerPassword: ${{ secrets.dockerpassword }}
	imageName: openrct2/openrct2.api
	fullbranch: ${{ github.ref }}
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	- name: Build image
	run: docker build -t "$imageName" .
	- name: Push image
	run: \|
	branch=$(echo $fullbranch \| sed 's/refs\/heads\///')
	echo "Current branch is $branch"
	if [ $branch == 'master' ]; then
	docker login -u "$dockerId" -p "$dockerPassword"
	docker push "$imageName"
	else
	echo 'Image not pushed'
	fi

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