Expiration Date misbehaves when the client is misconfigured

[EncryptedGiraffe]

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Describe the bug
The expiration time for forms appears to depend on the end user's computer settings, which causes inconsistencies in the true expiry time for forms, in the case that the user's computer clock is misconfigured.

To Reproduce
Steps to reproduce the behavior:

1. Set a form to expire at a certain time.
2. Change your computer clock to be in the future.
3. Attempt to view the form.
4. Be unable to see the form, since your computer thinks it has expired.

Expected behavior
The form's expiration time should be calculated by the server, according to the server's timezone, and should not be affected by the client's (potentially incorrect) time settings.

Nextcloud (please complete the following information):

• Nextcloud-Version: 34.0.3
• Forms-Version: 5.3.5