style: enforce no_whitespace_in_blank_line

https://cs.symfony.com/doc/rules/whitespace/no_whitespace_in_blank_line.html

Signed-off-by: Daniel Kesselberg <mail@danielkesselberg.de>

Author: kesselb

CHANGELOG.md

@@ -1,6 +1,10 @@
 # Changelog
 All notable changes to this project will be documented in this file.
 
+## 1.3.3 — unreleased
+### Added
+* `no_whitespace_in_blank_line`: Remove trailing whitespace at the end of blank lines
+
 ## 1.3.2 - 2024-10-14
 ### Added
 * `type_declaration_spaces`: A single space between typehint and variable name

src/Config.php

@@ -55,6 +55,7 @@ public function getRules() : array {
 			'no_trailing_whitespace' => true,
 			'no_trailing_whitespace_in_comment' => true,
 			'no_unused_imports' => true,
+			'no_whitespace_in_blank_line' => true,
 			'nullable_type_declaration_for_default_null_value' => true,
 			'nullable_type_declaration' => ['syntax' => 'question_mark'],
 			'operator_linebreak' => [