fix: don't validate phone number uniqueness if nil #335

	name: "[CI] Lint"
	on: [push, pull_request]

	env:
	CI: "true"
	SIMPLECOV: "true"

	concurrency:
	group: ${{ github.workflow }}-${{ github.head_ref \|\| github.run_id }}
	cancel-in-progress: true

	jobs:
	lint:
	name: Lint code
	runs-on: ubuntu-20.04
	if: "!startsWith(github.head_ref, 'chore/l10n')"
	timeout-minutes: 60
	steps:
	- uses: actions/checkout@v2.0.0
	with:
	fetch-depth: 1
	- uses: ruby/setup-ruby@v1
	with:
	bundler-cache: true
	- uses: actions/setup-node@v1
	- name: Get npm cache directory path
	id: npm-cache-dir-path
	run: echo "::set-output name=dir::$(npm get cache)-lint"
	- uses: actions/cache@v2
	id: npm-cache
	with:
	path: ${{ steps.npm-cache-dir-path.outputs.dir }}
	key: npm-${{ hashFiles('**/package-lock.json') }}
	restore-keys: \|
	npm-
	- name: Install JS dependencies
	run: npm ci
	- run: bundle exec rubocop -P
	name: Lint Ruby files

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