Update Connection.php

The startSession method has only one parameter pass

Author: spzgy

src/Connection.php

@@ -577,7 +577,7 @@ public function getSession()
  */
  public function startTransaction($transactionOptions = [], $sessionOptions = [])
  {
- $session = $this->startSession($sessionOptions,true);
+ $session = $this->startSession($sessionOptions);
  $session->getTransaction()->start($transactionOptions);
  return $session;
  }