Add new practice exercise `rotational-cipher` #871

	name: elm / pr

	on:
	pull_request:
	push:
	branches: [main]

	jobs:
	ci:
	runs-on: ubuntu-22.04

	strategy:
	matrix:
	node-version: [12.x, 14.x, 16.x]

	steps:
	- name: Checkout PR
	uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332

	- name: Use Node.js ${{ matrix.node-version }}
	uses: actions/setup-node@1e60f620b9541d16bece96c5465dc8ee9832be0b
	with:
	node-version: ${{ matrix.node-version }}

	- name: Install elm + tools and cache the ELM_HOME directory
	uses: mpizenberg/elm-tooling-action@809c844d494c95906eb8cafcfa0060b29193709d
	with:
	cache-key: elm-${{ matrix.node-version }}-${{ hashFiles('elm-tooling.json', 'template/elm.json') }}
	cache-restore-key: elm-${{ matrix.node-version }}

	- name: Check that everything is alright
	run: bin/build.sh

	elm-test-runner:
	runs-on: ubuntu-22.04

	steps:
	- name: Checkout exercism/elm
	uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332

	- name: Run tests for all exercises
	run: bin/run-all-exercises-in-docker.sh

	elm-analyzer:
	runs-on: ubuntu-22.04

	steps:
	- name: Checkout exercism/elm
	uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332

	- name: Run tests for all exercises
	run: bin/analyze-all-exercises-in-docker.sh

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