Add helpful message when `ProductManifold` is used without RAT.jl #723

	name: Documenter
	on:
	push:
	branches: [master]
	tags: [v*]
	pull_request:

	jobs:
	docs:
	name: Documentation
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: quarto-dev/quarto-actions/setup@v2
	with:
	version: "1.5.55"
	- uses: julia-actions/setup-julia@latest
	with:
	version: "1.10"
	- name: Julia Cache
	uses: julia-actions/cache@v2
	- name: Cache Quarto
	id: cache-quarto
	uses: actions/cache@v4
	env:
	cache-name: cache-quarto
	with:
	path: tutorials/_freeze
	key: ${{ runner.os }}-${{ env.cache-name }}-${{ hashFiles('tutorials/*.qmd') }}
	restore-keys: \|
	${{ runner.os }}-${{ env.cache-name }}-
	- name: Cache Documenter
	id: cache-documenter
	uses: actions/cache@v4
	env:
	cache-name: cache-documenter
	with:
	path: docs/src/tutorials
	key: ${{ runner.os }}-${{ env.cache-name }}-${{ hashFiles('tutorials/*.qmd') }}
	restore-keys: \|
	${{ runner.os }}-${{ env.cache-name }}-
	- name: Cache CondaPkg
	id: cache-condaPkg
	uses: actions/cache@v4
	env:
	cache-name: cache-condapkg
	with:
	path: docs/.CondaPkg
	key: ${{ runner.os }}-${{ env.cache-name }}-${{ hashFiles('docs/CondaPkg.toml') }}
	restore-keys: \|
	${{ runner.os }}-${{ env.cache-name }}-
	- name: "Documenter rendering (including Quarto)"
	run: "docs/make.jl --quarto"
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	DOCUMENTER_KEY: ${{ secrets.DOCUMENTER_KEY }}

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