avro

Bump underscore from 1.12.1 to 1.13.0 in /lang/js

Bumps [underscore](https://github.com/jashkenas/underscore) from 1.12.1 to 1.13.0.
- [Release notes](https://github.com/jashkenas/underscore/releases)
- [Commits](https://github.com/jashkenas/underscore/compare/1.12.1...1.13.0)

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