Resolve dependency without npm install

[mikicho]

Hey,
I want to reduce my build time and remove the npm install step from my build, to my understanding, WhiteSource does not need the dependencies installed (i.e. node_modules folder) to resolve dependencies because it smart to use npm ls, so I don't understand why the FSA npm resolver ignore unmet dependencies in this line: https://github.com/whitesource/fs-agent/blob/master/src/main/java/org/whitesource/agent/dependency/resolver/npm/NpmLsJsonDependencyCollector.java#L251

thanks.