Merge pull request #7 from Avametix/fix/logout

Author: PixNyb

src/Avametix/DirectApi.php

@@ -67,7 +67,10 @@ public function login_as(string $username) {
      * @access public
      */
     public function logout() {
-        $this->usernames = array_splice($this->usernames, 0, 1);
+        if (count($this->usernames) < 2)
+            return;
+            
+        array_splice($this->usernames, 1, 1);
     }
 
     /**