Create unit tests for standard deviation and variance aggregates and check correct behavior of the aggregates.

[ThomasNehring]

Type of issue

• [ ] Bug
• [X] Enhancement
• [ ] Compliance
• [ ] Question
• [ ] Help wanted

Current Behavior

There is no unit test for processed data, but there is a bug report (#2360) for the standard deviation and variance aggregates, which could be fixed only partially without being able to test this.

Expected Behavior

A unit test is in place which is testing the standard deviation and variance aggregates (both for sample and population) and at least ensures that the examples provided in the spec (v 1.05, part 13, A.35 - A.38) are calculated correctly.

Steps To Reproduce

No response

Environment

- OS: any
- Environment:
- Runtime:
- Nuget Version:
- Component:
- Server:
- Client:

Anything else?

No response