Support Laravel 8 (#222)

* Update for laravel 8

* Update readme

.github/workflows/run-tests.yml

@@ -4,20 +4,7 @@ on: [push, pull_request]
 
 jobs:
   test:
-    runs-on: ${{ matrix.os }}
-    strategy:
-      fail-fast: true
-      matrix:
-        php: [7.2, 7.3, 7.4]
-        os: [ubuntu-latest]
-        laravel: [6.*, 7.*]
-        include:
-          - laravel: 6.*
-            testbench: 4.*
-          - laravel: 7.*
-            testbench: 5.*
-
-    name: PHP${{ matrix.php }} - ${{ matrix.dependency-version }}
+    runs-on: ubuntu-latest
 
     steps:
       - name: Checkout code
@@ -26,14 +13,12 @@ jobs:
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
-          php-version: ${{ matrix.php }}
+          php-version: 8.0
           extensions: dom, curl, libxml, mbstring, zip, pcntl, pdo, sqlite, pdo_sqlite
           coverage: none
 
       - name: Install Composer dependencies
-        run: |
-          composer require "laravel/framework:${{ matrix.laravel }}" "orchestra/testbench:${{ matrix.testbench }}" --no-interaction --no-update
-          composer update --prefer-dist --no-interaction --no-suggest
+        run: composer install --prefer-dist --no-interaction
 
       - name: Execute tests
         run: vendor/bin/phpunit

composer.json

@@ -10,12 +10,13 @@
         }
     ],
     "require": {
-        "php": "^7.2|^7.3|^7.4",
-        "illuminate/support": "^6.0|^7.0"
+        "php": "^8.0",
+        "illuminate/support": "^8.0",
+        "laravel/legacy-factories": "^1.3"
     },
     "require-dev": {
-        "orchestra/testbench": "^4.0",
-        "phpunit/phpunit": "^8.0",
+        "orchestra/testbench": "^6.0",
+        "phpunit/phpunit": "^9.0",
         "mockery/mockery": "^1.0.0"
     },
     "autoload": {