Allow sorting events/alerts based on aggregation time range.

[dennisoelkers]

Description

Motivation and Context

This PR enables sorting alerts/events based on aggregation time range both in the front- and backend.

The sorting for this field needs to be created so that both timerange_start & timerange_end are taken into account.

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring (non-breaking change)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.