[Bug]: Validator does not raise warning for missing time zone

[stephprince]

What happened?

See the original issue here: https://github.com/NeurodataWithoutBorders/pynwb/issues/2084.

The validator currently does not raise a warning if a datetime is provided without required time zone information. I think this would require an update to the HDMF validator

Steps to Reproduce

See the original issue.

Operating System

macOS

Python Version

3.13

Package Versions

No response

[mavaylon1]

@stephprince How much of a priority is this?