Remove unused SettingsController::convertStylesToString method

[MAILPOET-5798]

mailpoet/lib/EmailEditor/Engine/SettingsController.php

@@ -103,17 +103,6 @@ class SettingsController {
     return "{$width}px";
   }
 
-  /**
-   * This functions converts an array of styles to a string that can be used in HTML.
-   */
-  public function convertStylesToString(array $styles): string {
-    $cssString = '';
-    foreach ($styles as $property => $value) {
-      $cssString .= $property . ':' . $value . ';';
-    }
-    return trim($cssString); // Remove trailing space and return the formatted string
-  }
-
   public function parseStylesToArray(string $styles): array {
     $styles = explode(';', $styles);
     $parsedStyles = [];