update the isSMTPConnected() method to also check for a false value

Author: michalsn

system/Email/Email.php

@@ -2292,6 +2292,8 @@ protected function setArchiveValues(): array
      */
     protected function isSMTPConnected(): bool
     {
-        return $this->SMTPConnect !== null && get_debug_type($this->SMTPConnect) !== 'resource (closed)';
+        return $this->SMTPConnect !== null
+            && $this->SMTPConnect !== false
+            && get_debug_type($this->SMTPConnect) !== 'resource (closed)';
     }
 }