semver not declared as dependency in package.json

[jrmerz]

Environment details

• OS: Debian/Linux
• Node.js version: v8.11.4
• npm version: 5.6.0
• google-gax version: 0.19.0

Steps to reproduce

semver is not declared as a dependency in the package.json file but required here and while it is a dependency of grpc, my project has a conflict dependency on semver and neither are promoted to the root node_modules dir causing the following error:

Error: Cannot find module 'semver'
    at Function.Module._resolveFilename (module.js:547:15)
    at Function.Module._load (module.js:474:25)
    at Module.require (module.js:596:17)
    at require (internal/module.js:11:18)
    at Object.<anonymous> (/service/node_modules/google-gax/build/src/grpc.js:87:14)
    at Module._compile (module.js:652:30)
    at Object.Module._extensions..js (module.js:663:10)
    at Module.load (module.js:565:32)
    at tryModuleLoad (module.js:505:12)
    at Function.Module._load (module.js:497:3)