GitHub Action for running PHP_CodeSniffer on pull requests with annotations

phpcs.yml

name: PHP_CodeSniffer

on: pull_request

jobs:
  phpcs:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v2

      - name: Setup PHP
        uses: shivammathur/setup-php@v2
        with:
          php-version: '7.3'
          coverage: none
          tools: composer, cs2pr

      - name: Get Composer cache directory
        id: composer-cache
        run: echo "::set-output name=dir::$(composer config cache-files-dir)"

      - name: Setup cache
        uses: pat-s/always-upload-cache@v1.1.4
        with:
          path: ${{ steps.composer-cache.outputs.dir }}
          # Use the hash of composer.json as the key for your cache if you do not commit composer.lock. 
          # key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.json') }}
          key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.lock') }}
          restore-keys: ${{ runner.os }}-composer-

      - name: Install dependencies
        run: composer install --prefer-dist --no-suggest --no-progress

      - name: Detect coding standard violations
        run: vendor/bin/phpcs -q --report=checkstyle | cs2pr --graceful-warnings

Blog post: https://dominikschilling.de/schnipsel/github-action-workflow-php-codesniffer-check-annotations/

I played also a with actions. But it works easier for me if I leave the phpcs run inside the composer.json and request this inside the workflow file for the actions. So is it easier to play local and via actions on GitHub with the same scripts and tests.
The follow example should demonstrate this, run currently in this repo https://github.com/bueltge/marksimple/actions

composer config

        "scripts": {
        "cs": "@php ./vendor/squizlabs/php_codesniffer/bin/phpcs",
        "pu": "@php ./vendor/bin/phpunit",
        "qa": ["@cs", "@pu"]
    }

workflow

    - name: Run QA Scripts from composer.json
      run: composer qa

I see cache is missing here which on big projects saves a lot of time