Bump extend from 3.0.1 to 3.0.2 in /blackboxtest

Bumps [extend](https://github.com/justmoon/node-extend) from 3.0.1 to 3.0.2.
- [Release notes](https://github.com/justmoon/node-extend/releases)
- [Changelog](https://github.com/justmoon/node-extend/blob/master/CHANGELOG.md)
- [Commits](https://github.com/justmoon/node-extend/compare/v3.0.1...v3.0.2

)

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