Enhance the new embargo area feature

Description of the issue

Since https://github.com/OpenEnergyPlatform/oeplatform/pull/1534 we have introduced the embargo area. This feature affects most of the functions of a table if an Embargo period is set.

• Restricted user interface: no download possible, data is not visible to the user
• Restricted API: all CRUD functions are not available - no one can add or read data for a table

It is also not yet clear how to deal with tables for which the embargo period has expired.

Ideas of solution

Specify the complete embargo area process. Enable table access for users who have table permissions and implement a notification system to receive a user response indicating what to do with data whose embargo period has expired

Workflow checklist

• I am aware of the workflow in CONTRIBUTING.md