Change the contract's trial end

Usage Advisory:

• This endpoint is limited in scope: it does not affect the start dates of component subscriptions, metered usages, or discounts.
• Effective only when there are no phase changes post-trial end.
• Given the evolving nature of our features, there may be additional, unforeseen limitations.
• It exclusively modifies the trial phase; exercise caution with complex contracts involving components and discounts.
  

Please use this endpoint judiciously to ensure it aligns with your specific contract structures and requirements.