Function logout

logout(): Promise<void>
JMap.User.logout

Logout function. Make a call to the server to invalidate the session id.

If an error occurs, 2 differents string message can be returned :
- "user.logout.error.server" => Unexpected error while requesting the server
- "user.logout.error.unexpected" => Unexpected error client side
Returns Promise<void>
Example
```
// Close the user session client and server side
JMap.User
   .logout()
   .then(() => {
     console.log(`User has been logout`)
   })
```