Apply php-cs-fixer fixers

- braces
- function_declaration
- lowercase_keywords
- method_argument_space
- no_spaces_inside_parenthesis
- no_trailing_whitespace
- no_trailing_whitespace_in_comment
- single_blank_line_at_eof

tests/TestCase.php

@@ -70,4 +70,4 @@ abstract class TestCase extends \PHPUnit\Framework\TestCase
 
         return $contents;
     }
-}
+}