feat: improve labels for scope and missing deps

[xzhou-snyk]

Our labels don't seem to be consistent:

• When it is dev dependency, the missingLockFileEntry is missed out. This is clearly a bug because this label was there all the way for both prod and dev deps after we call the createDepTrees method.
• The scope label is missed out in a missing sub dep.

This PR fixed the above two label issues and add a bunch of corresponding tests. In addition, node version in CI is raised to 16 (together with some bumping up of dev deps) in order to be able to do future release.

[snyksec]

:tada: This PR is included in version 1.44.0 :tada:

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot :package::rocket: