Add CI action to publish custom-branch hydra-node docker images #4185

	name: Check code formatting

	on:
	# We're using merge-chains; so this needs to run then.
	merge_group:
	pull_request:

	jobs:
	formatting:
	name: Check code formatting
	runs-on: ubuntu-latest
	steps:
	- name: 📥 Checkout repository
	uses: actions/checkout@v4

	- name: ❄ Prepare nix
	uses: cachix/install-nix-action@v30
	with:
	extra_nix_config: \|
	accept-flake-config = true
	log-lines = 1000

	- name: ❄ Cachix cache of nix derivations
	uses: cachix/cachix-action@v15
	with:
	name: cardano-scaling
	authToken: '${{ secrets.CACHIX_CARDANO_SCALING_AUTH_TOKEN }}'

	- name: 📐 Check code formatting
	run: \|
	nix build .#checks.x86_64-linux.treefmt

	- name: 📐 Check hlint
	run: \|
	nix build .#checks.x86_64-linux.hlint

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