Document the process for adding `ADD_TO_PROJECT_PAT` token #10

	name: Add issues to project board

	on:
	# Allow this workflow to be called by another workflow
	workflow_call:
	inputs:
	project-url:
	description: 'The URL of the project board to add the issue to'
	required: true
	type: string
	secrets:
	GITHUB_PAT:
	description: 'The github token with permissions to add issues to the project'
	required: true
	# The caller should use these triggers on their workflow file
	issues:
	types:
	- opened

	env:
	# We use this workflow locally for hugrverse-actions issues.
	# This variable detects whether we are running the workflow locally or via an external workflow_call.
	#
	# Github's terrible version of a 'ternary operator'
	# https://github.com/actions/runner/issues/409#issuecomment-752775072
	PROJECT_URL: ${{ github.repository == 'CQCL/hugrverse-actions' && 'https://github.com/orgs/CQCL-DEV/projects/10' \|\| inputs.project-url }}
	# We use a ADD_TO_PROJECT_PAT secret locally.
	GITHUB_TOKEN: ${{ secrets.GITHUB_PAT \|\| secrets.ADD_TO_PROJECT_PAT }}

	jobs:
	add-to-project:
	name: Add issue to project
	runs-on: ubuntu-latest
	steps:
	- name: Fail if project-url is not set
	if: env.PROJECT_URL == ''
	run: \|
	echo "The project-url input is required."
	exit 1
	- name: Fail if GITHUB_PAT is not set
	if: env.GITHUB_TOKEN == ''
	run: \|
	echo "The GITHUB_PAT input is required."
	exit 1
	- uses: actions/[email protected]
	with:
	project-url: ${{ env.PROJECT_URL }}
	github-token: ${{ env.GITHUB_TOKEN }}

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