Support for different timezones

[samiralavi]

The timestamp of the experiments when they are stored in the database is localized, which could be problematic for certain use cases that require showing the experiments in different time zones. This can be fixed by saving the UTC datetimes in the database and only convert them to the local time zone when displaying them.

Definition of Done:

• Stored datetime in database in UTC
• Display time on the frontend in local time zone