fix: package.json to reduce vulnerabilities
fix: package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/npm:ms:20170412

Latest report for perimeterx/perimeterx-node-express:
https://snyk.io/test/github/perimeterx/perimeterx-node-express
PerimeterX/perimeterx-node-express