Merge pull request #2728 from evan70/master

trim(): Passing null to parameter  ($string) of type string is deprecated

src/PHPMailer.php

@@ -1288,7 +1288,7 @@ class PHPMailer
      */
     public function setFrom($address, $name = '', $auto = true)
     {
-        $address = trim($address);
+        $address = trim((string)$address);
         $name = trim(preg_replace('/[\r\n]+/', '', $name)); //Strip breaks and trim
         //Don't validate now addresses with IDN. Will be done in send().
         $pos = strrpos($address, '@');