Switch CI to GitHub Actions

Author: Liam Hammett

.github/workflows/main.yml

@@ -0,0 +1,41 @@
+name: Run Tests
+on: [push]
+
+jobs:
+  run:
+    runs-on: ubuntu-latest
+    strategy:
+      max-parallel: 15
+      fail-fast: false
+      matrix:
+        php-versions: ["7.1", "7.2", "7.3", "7.4"]
+        composer-flags: ["--prefer-lowest", "--prefer-stable"]
+        env:
+          - LARAVEL_VERSION='~5.5'
+          - LARAVEL_VERSION='~5.6'
+          - LARAVEL_VERSION='~5.7'
+          - LARAVEL_VERSION='~5.8'
+          - LARAVEL_VERSION='^6.0'
+          - LARAVEL_VERSION='^7.0'
+        exclude:
+          - php-versions: 7.1
+            env: LARAVEL_VERSION='^6.0'
+          - php-versions: 7.1
+            env: LARAVEL_VERSION='^7.0'
+    name: Test on PHP ${{ matrix.php-versions }}, Laravel ${{ matrix.laravel-versions }} and ${{ matrix.composer-flags }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@master
+      - name: Install PHP
+        uses: shivammathur/setup-php@master
+        with:
+          php-version: ${{ matrix.php-versions }}
+      - name: Install Dependencies
+        run: |
+          ${{ matrix.env }}
+          composer config discard-changes true
+          composer self-update
+          composer require --dev "laravel/framework:${LARAVEL_VERSION}" --no-interaction --no-update
+          composer update ${{ matrix.composer-flags }} --prefer-dist --no-suggest --no-interaction
+      - name: Run PHPUnit
+        run: php vendor/bin/phpunit