OptimalDb v1.84

Bump NUnit from 3.13.3 to 4.5.1

---
updated-dependencies:
- dependency-name: NUnit
  dependency-version: 4.5.1
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>