Comparable enum (#20)

* feat: comparable enum

* test: comparable enum

* ci: php-cs-fixer in repository scope

* chore: add `Comparable` usage in README

* ci: globally use `php-cs-fixer`

* improve Comparable logic

* test more PHP versions in CI

* update ci job name

* remove class name quoting in exceptions to match PHP behavior

* migrate pest config

* add comment to test

---------

Co-authored-by: Samuel Štancl <samuel@archte.ch>
Co-authored-by: Samuel Štancl <samuel.stancl@gmail.com>

.github/workflows/ci.yml

@@ -12,14 +12,24 @@ on:
 
 jobs:
   pest:
-    name: Tests (Pest) L${{ matrix.laravel }}
+    name: Tests (Pest) PHP${{ matrix.php }} L${{ matrix.laravel }}
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        laravel: [9, 10]
+        include:
+          - laravel: 10
+            php: 8.1
+          - laravel: 10
+            php: 8.2
+          - laravel: 10
+            php: 8.3
 
     steps:
     - uses: actions/checkout@v2
+    - name: Setup PHP
+      uses: shivammathur/setup-php@v2
+      with:
+        php-version: ${{matrix.php}}
     - name: Install composer dependencies
       run: composer require "illuminate/support:^${{ matrix.laravel }}.0"
     - name: Run tests