Replace travis ci with github actions

.github/workflows/run-tests.yml

@@ -0,0 +1,43 @@
+name: Unit Tests
+
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - "*"
+  schedule:
+  - cron: '0 0 * * *'
+
+jobs:
+  php-tests:
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    env:
+      COMPOSER_NO_INTERACTION: 1
+
+    strategy:
+      matrix:
+        php: [7.3, 7.2]
+        dependency-version: [prefer-lowest, prefer-stable]
+
+    name: P${{ matrix.php }} - ${{ matrix.dependency-version }}
+
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v3
+
+    - name: Setup PHP
+      uses: shivammathur/setup-php@v2
+      with:
+        php-version: ${{ matrix.php }}
+        coverage: xdebug
+        tools: composer:v2
+
+    - name: Install dependencies
+      run: |
+        composer update --${{ matrix.dependency-version }} --prefer-dist
+
+    - name: Execute Unit Tests
+      run: composer test

README.md

@@ -2,7 +2,7 @@
 
 **Braintree driver for the Omnipay PHP payment processing library**
 
-[![Build Status](https://travis-ci.org/thephpleague/omnipay-braintree.svg?branch=master)](https://travis-ci.org/thephpleague/omnipay-braintree)
+[![Unit Tests](https://github.com/thephpleague/omnipay-braintree/actions/workflows/run-tests.yml/badge.svg)](https://github.com/thephpleague/omnipay-braintree/actions/workflows/run-tests.yml)
 [![Latest Stable Version](https://poser.pugx.org/omnipay/braintree/version.png)](https://packagist.org/packages/omnipay/braintree)
 [![Total Downloads](https://poser.pugx.org/omnipay/braintree/d/total.png)](https://packagist.org/packages/omnipay/braintree)
 

composer.json

@@ -41,5 +41,11 @@
         "branch-alias": {
             "dev-master": "4.0.x-dev"
         }
+    },
+    "scripts": {
+        "test": [
+            "@putenv XDEBUG_MODE=coverage",
+            "vendor/bin/phpunit --coverage-text --coverage-clover=coverage.clover"
+        ]
     }
 }