[#370] Add ability to advance level in Nettest

Description

After !751 (merged) was merged we still have no ability to advance level in Nettest the same way we do it with time.

Related issue(s)

Resolves #370 (closed) part 3

✅ Checklist for your Merge Request

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• Tests (see short guidelines)

  • If I added new functionality, I added tests covering it.
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