feat: basic leanpub generation #237

	name: Validate Pull Request

	# This workflow verifies that the site will build for pull requests.
	on: [pull_request]

	jobs:
	validate-pull-request:
	runs-on: ubuntu-20.04
	steps:
	- name: Checkout
	uses: actions/checkout@v3

	# Fixup Git URLs, see:
	# https://stackoverflow.com/questions/70663523/the-unauthenticated-git-protocol-on-port-9418-is-no-longer-supported
	- name: Fix up git URLs
	run: echo -e '[url "https://github.com/"]\n insteadOf = "git://github.com/"' >> ~/.gitconfig

	# Check typescript compiles properly.
	- name: Check TypeScript
	run: make typescript-check

	# Run the build - this will fail if there are broken links etc.
	- name: Build
	run: make build

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