Create time off request Params change

Introducing an important fix to the Create time off request method:

1. Removing the policy type id and the user id from the URL params.
2. Adding the policy type id and the user id to the body params.
3. Updated URL - https://api.connecteam.com/time-off/v1/requests

This important fix was implemented to provide better support for the upcoming Update Time Off Request method, which is already under development. An email has been sent to the relevant clients who were using this endpoint prior to the change.