Bump express from 4.19.2 to 4.21.0 #6

	name: 'Check content-linter rules docs'

	# What it does: Makes sure the content-linter-rules.md is up-to-date.
	# Why we have it: So what's automated doesn't fall behind
	# Who does it impact: Docs content.

	on:
	workflow_dispatch:
	pull_request:
	paths:
	- 'src/content-linter/**'
	# In case imported markdownlint rules are updated
	- package-lock.json
	# In case manual changes are made to the content-linter-rules.md file
	- data/reusables/contributing/content-linter-rules.md
	# Self-test
	- .github/workflows/content-linter-rules-docs.yml

	permissions:
	contents: read

	jobs:
	check-content-linter-rules-docs:
	runs-on: ${{ fromJSON('["ubuntu-latest", "ubuntu-20.04-xl"]')[github.repository == 'github/docs-internal'] }}
	if: github.repository == 'github/docs-internal' \|\| github.repository == 'github/docs'
	steps:
	- name: Checkout
	uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1

	- uses: ./.github/actions/node-npm-setup

	- name: Check that content-linter-rules.md is up-to-date
	run: npm run generate-content-linter-docs

	- name: Fail if it isn't up-to-date
	run: \|
	if [ -n "$(git status --porcelain)" ]; then
	git status
	git diff

	# Some whitespace for the sake of the message below
	echo ""
	echo ""

	echo "content-linter-rules.md is out of date."
	echo "Please run 'npm run generate-content-linter-docs' and commit the changes."
	exit 1;
	fi

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