[Asl] Fix pattern for string types and improve error message #958

	name: Check format with `dune fmt`

	# Copy-pasted from https://stackoverflow.com/questions/66335225/how-to-cancel-previous-runs-in-the-pr-when-you-push-new-commitsupdate-the-curre
	concurrency:
	group: ${{ github.workflow }}-${{ github.event.pull_request.number \|\| github.ref }}
	cancel-in-progress: true

	on:
	pull_request:
	# push:
	workflow_dispatch:
	schedule:
	# Prime the caches every Monday
	- cron: 0 1 * * MON

	permissions: read-all

	jobs:
	build:
	runs-on: ubuntu-latest

	steps:
	- name: Checkout tree
	uses: actions/checkout@v4

	- name: Set-up OCaml
	uses: ocaml/setup-ocaml@v2
	with:
	ocaml-compiler: 5.1

	- run: opam install dune ocamlformat.0.26.2

	- run: opam exec -- dune fmt

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