Add API tests

tests/TextTest.php

@@ -5,15 +5,12 @@
 
 namespace Friendica\Test;
 
-// backward compatibility
-if (!class_exists('\PHPUnit\Framework\TestCase')) {
-    class_alias('\PHPUnit_Framework_TestCase', '\PHPUnit\Framework\TestCase');
-}
+use PHPUnit\Framework\TestCase;
 
 /**
  * Tests for text functions.
  */
-class TextTest extends \PHPUnit\Framework\TestCase
+class TextTest extends TestCase
 {
 
 	/**