Smtp : il there is a connection error, reset the connection socket to not send multiple packets to closed socket (and generate associated errors)

src/Smtp.php

@@ -106,6 +106,7 @@ class Smtp
             if ($errstr === "" && $php_errormsg !== "") {
                 $errstr = $php_errormsg;
             }
+            $this->smtpStream = null;
             throw new \Exception(sprintf(dgettext(
                 "domframework",
                 "Can't connect to SMTP server : %s"
@@ -139,6 +140,7 @@ class Smtp
                     ) ===
                     false
                 ) {
+                    $this->smtpStream = null;
                     throw new \Exception(sprintf(dgettext(
                         "domframework",
                         "Can't activate STARTTLS %s"
@@ -148,6 +150,7 @@ class Smtp
                 $this->debug("STARTTLS ACTIVATED\n");
             }
         } elseif ($this->starttls === "encrypt") {
+            $this->smtpStream = null;
             throw new \Exception(dgettext(
                 "domframework",
                 "Server doesn't supports STARTTLS"
@@ -170,6 +173,7 @@ class Smtp
                 $this->putLine("AUTH LOGIN " . base64_encode($this->user) . "\r\n");
                 $this->putLine(base64_encode($this->password) . "\r\n");
             } else {
+                $this->smtpStream = null;
                 throw new \Exception(
                     dgettext(
                         "domframework",