Bump submodules/privacy-reference-tests from 6133e7d to a75e09f

Bumps [submodules/privacy-reference-tests](https://github.com/duckduckgo/privacy-reference-tests) from `6133e7d` to `a75e09f`.
- [Release notes](https://github.com/duckduckgo/privacy-reference-tests/releases)
- [Commits](duckduckgo/privacy-reference-tests@6133e7d...a75e09f)

---
updated-dependencies:
- dependency-name: submodules/privacy-reference-tests
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>