Bump json-schema and jsprim

Bumps [json-schema](https://github.com/kriszyp/json-schema) and [jsprim](https://github.com/joyent/node-jsprim). These dependencies needed to be updated together. Updates `json-schema` from 0.2.3 to 0.4.0 - [Release notes](https://github.com/kriszyp/json-schema/releases) - [Commits](kriszyp/json-schema@v0.2.3...v0.4.0) Updates `jsprim` from 1.4.1 to 1.4.2 - [Release notes](https://github.com/joyent/node-jsprim/releases) - [Changelog](https://github.com/TritonDataCenter/node-jsprim/blob/v1.4.2/CHANGES.md) - [Commits](TritonDataCenter/node-jsprim@v1.4.1...v1.4.2) --- updated-dependencies: - dependency-name: json-schema dependency-type: indirect - dependency-name: jsprim dependency-type: indirect ... Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]