univalue unit tests were added in #4730 , and exist at `/src/test/univalue_tests.cpp` (outside the univalue tree). That test was brought into the univalue repository in https://github.com/bitcoin-core/univalue/pull/4 , which was pulled into the github repository in https://github.com/bitcoin/bitcoin/pull/11420.

That means that the univalue test exists in two places:
1. `/src/test/univalue_tests.cpp`
2. `/src/univalue/test/object.cpp`

(2) is a strict superset of (1). It adds some macros to work around boost not being a univalue dependency, and adds a few extra lines of test.

Therefore remove `/src/test/univalue_tests.cpp`

make check
ninja check