Fix/cert return

[mrrobot47]

This pull request makes minor improvements to the Site_Letsencrypt.php helper by ensuring that the executeFirstRequest and executeRenewal methods consistently return true upon successful completion. This helps clarify the expected return value and can improve error handling or control flow in code that calls these methods.

• Consistency improvements:
  • Added a return true; statement at the end of the executeFirstRequest method to explicitly indicate successful completion.
  • Added a return true; statement at the end of the try block in the executeRenewal method, before the exception handling, to signal successful execution.