Add test to ensure that multi-line blocks get matched in PHP

Author: westonruter

phpunit/class-dynamic-blocks-render-test.php

@@ -88,7 +88,7 @@ function test_dynamic_block_rendering_with_content() {
 		register_block_type( 'core/dummy', $settings );
 		$post_content =
 			'before' .
-			'<!-- wp:core/dummy value="b1" -->this should be ignored<!-- /wp:core/dummy -->' .
+			"<!-- wp:core/dummy value=\"b1\" -->this\nshould\n\nbe\nignored<!-- /wp:core/dummy -->" .
 			'between' .
 			'<!-- wp:core/dummy value="b2" -->this should also be ignored<!-- /wp:core/dummy -->' .
 			'after';