Add technical documentation for migration framework #157

	# SPDX-FileCopyrightText: 2023 The Crossplane Authors <https://crossplane.io>
	#
	# SPDX-License-Identifier: CC0-1.0

	name: Backport

	on:
	# NOTE(negz): This is a risky target, but we run this action only when and if
	# a PR is closed, then filter down to specifically merged PRs. We also don't
	# invoke any scripts, etc from within the repo. I believe the fact that we'll
	# be able to review PRs before this runs makes this fairly safe.
	# https://securitylab.github.com/research/github-actions-preventing-pwn-requests/
	pull_request_target:
	types: [closed]
	# See also commands.yml for the /backport triggered variant of this workflow.

	jobs:
	# NOTE(negz): I tested many backport GitHub actions before landing on this
	# one. Many do not support merge commits, or do not support pull requests with
	# more than one commit. This one does. It also handily links backport PRs with
	# new PRs, and provides commentary and instructions when it can't backport.
	# The main gotchas with this action are that it _only_ supports merge commits,
	# and that PRs _must_ be labelled before they're merged to trigger a backport.
	open-pr:
	runs-on: ubuntu-20.04
	if: github.event.pull_request.merged
	steps:
	- name: Checkout
	uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 #v3
	with:
	fetch-depth: 0

	- name: Open Backport PR
	uses: zeebe-io/[email protected]
	with:
	github_token: ${{ secrets.GITHUB_TOKEN }}
	github_workspace: ${{ github.workspace }}
	version: v0.0.4

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