* [libraries] move all the unit tests into test/unit
* [settings] remove empty test file
* [mongo-utils] remove test setup as there are no tests
* [libraries] ensure that all libraries with tests have test/setup.js
* [monorepo] remove test step from Cloud build for libraries without tests
GitOrigin-RevId: b9a0a8a3330db7d8646c7a272b03fbb8c5e44bc0