Use type hints for TypeError exception

This change allows to replace the Assert::parameterType by a type hint
in Ie215179b4631fd9071b257772c5cb193547cb7d7.

Change-Id: I399a92d3fac0e0849fe3a403c703fe7d32f51257

tests/phpunit/ULSJsonMessageLoaderTest.php

@@ -15,14 +15,14 @@ class ULSJsonMessageLoaderTest extends \PHPUnit\Framework\TestCase {
 	public function testGetFilenamesWithBadInput() {
 		$instance = new ULSJsonMessageLoader();
 
-		$this->expectException( \Exception::class );
+		$this->expectException( \TypeError::class );
 		$instance->getFilenames( null );
 	}
 
 	public function testGetMessagesWithBadInput() {
 		$instance = new ULSJsonMessageLoader();
 
-		$this->expectException( \Exception::class );
+		$this->expectException( \TypeError::class );
 		$instance->getMessages( null );
 	}