Create initial build-release workflow #1

	name: Build release

	on:
	workflow_dispatch:
	inputs:
	version:
	description: 'New version number eg: 5.0.0'
	required: true
	type: string
	pull_request:

	permissions:
	contents: write
	pull-requests: write

	jobs:
	build-release:
	name: Build release
	runs-on: Ubuntu-22.04

	steps:
	- name: Checkout
	uses: actions/checkout@v4.2.2

	- name: Install dependencies
	uses: ./.github/workflows/actions/install-node

	- name: Validate version
	# a script here to validate the parsed version no. using semver, both to
	# make sure it's a valid semver and to make sure it is sensibly sequential
	# node script? Shell script/command using semver's cli?
	run:

	- name: Update package version
	run: npm version --no-git-tag-version --workspace govuk-frontend ${{ inputs.version }}

	- name: Update CHANGELOG
	# Node (?) script to replace unreleased heading with version number and
	# create new unreleased heading.
	run:

	- name: Get release notes for release from CHANGELOG
	# Script to get contents of release from changelog. Could also be used for
	# version validation above?
	run:

	- name: Run tests
	run: npm run test

	- name: Build package
	run: npm run build:package

	- name: Build release
	run: npm run build:release

	- name: Create pull request
	uses: peter-evans/create-pull-request@v6
	with:
	token: ${{ secrets.GITHUB_TOKEN }}
	branch: release-${{ inputs.version }}
	delete-branch: true
	commit-message: 'Release ${{ inputs.version }}'
	title: 'Release ${{ inputs.version }}'
	body: ''
	base: ${{ github.head_ref }}

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