[ci] Move pregen steps into a composite action #4929

	name: Check Pregenerated Files

	on:
	pull_request:
	push:
	branches-ignore:
	- main

	concurrency:
	group: ${{ github.workflow }}-${{ github.head_ref \|\| github.ref }}
	cancel-in-progress: true

	jobs:
	update:
	name: "Update"
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0
	- name: Run pregen
	uses: ./.github/actions/pregen
	- name: Add untracked files to index so they count as changes
	run: git add -A
	- name: Check output
	run: git --no-pager diff --exit-code HEAD
	- name: Generate diff
	run: git diff HEAD > pregenerated-files-fixes.patch
	if: ${{ failure() }}
	- uses: actions/upload-artifact@v4
	with:
	name: pregenerated-files-fixes
	path: pregenerated-files-fixes.patch
	if: ${{ failure() }}

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