phpunit compatibility update

Author: Ken Seah

tests/BatchTest.php

@@ -1,8 +1,9 @@
 <?php
 
 use \DrewM\MailChimp\MailChimp;
+use PHPUnit\Framework\TestCase;
 
-class BatchTest extends PHPUnit_Framework_TestCase
+class BatchTest extends TestCase
 {
 
     public function setUp()
@@ -29,4 +30,4 @@ public function testNewBatch()
         $this->assertInstanceOf('DrewM\MailChimp\Batch', $Batch);
     }
 
-}
+}

tests/ListsTest.php

@@ -1,8 +1,9 @@
 <?php
 
 use \DrewM\MailChimp\MailChimp;
+use PHPUnit\Framework\TestCase;
 
-class ListsTest extends PHPUnit_Framework_TestCase
+class ListsTest extends TestCase
 {
 
     public function setUp()
@@ -29,4 +30,4 @@ public function testGetLists()
         $this->assertArrayHasKey('lists', $lists);
     }
 
-}
+}

tests/MailChimpTest.php

@@ -1,8 +1,9 @@
 <?php
 
 use \DrewM\MailChimp\MailChimp;
+use PHPUnit\Framework\TestCase;
 
-class MailChimpTest extends PHPUnit_Framework_TestCase
+class MailChimpTest extends TestCase
 {
 
     public function setUp()
@@ -18,7 +19,7 @@ public function setUp()
 
     public function testInvalidAPIKey()
     {
-        $this->setExpectedException('\Exception');
+        $this->expectException('\Exception');
         $MailChimp = new MailChimp('abc');
     }