Issue #2976345 by deviantintegral: Support tests on PHPUnit 4

tests/src/Unit/DrupalGuzzleCacheTest.php

@@ -109,13 +109,14 @@ class DrupalGuzzleCacheTest extends UnitTestCase {
    * Tests setting an invalid prefix.
    *
    * @covers ::setPrefix
+   *
+   * @expectedException \InvalidArgumentException
+   * @expectedExceptionMessage The cache key prefix cannot be longer than 191 characters.
    */
   public function testInvalidPrefix() {
     /** @var \Drupal\Core\Cache\CacheBackendInterface $backend */
     $backend = $this->createMock(CacheBackendInterface::class);
     $prefix = $this->getRandomGenerator()->name(192);
-    $this->expectException(\InvalidArgumentException::class);
-    $this->expectExceptionMessage('The cache key prefix cannot be longer than 191 characters.');
     new DrupalGuzzleCache($backend, $prefix);
   }