fix(npm): improvement logic for lockfile v2-v3

[DmitriyLewen]

Description

1. npm includes optional dependencies in dependency list, graph and node_modules folder. We also need to include them.
   e.g.
   graph:

   3840@ /home/dmitriy/work/temp/3840
   └─┬ cra-append-sw@2.7.0
     └─┬ webpack@4.46.0
       └─┬ watchpack@1.7.5
         ├─┬ chokidar@3.5.3
         │ └── glob-parent@5.1.2
         └─┬ watchpack-chokidar2@2.0.1
           └─┬ chokidar@2.1.8
             └── glob-parent@3.1.0
   

   package-lock.json file:

   ...
       "node_modules/watchpack": {
         "version": "1.7.5",
         "resolved": "https://registry.npmjs.org/watchpack/-/watchpack-1.7.5.tgz",
         "integrity": "sha512-9P3MWk6SrKjHsGkLT2KHXdQ/9SNkyoJbabxnKOoJepsvJjJG8uYTR3yTPxPQvNDI3w4Nz1xnE0TLHK4RIVe/MQ==",
         "dependencies": {
           "graceful-fs": "^4.1.2",
           "neo-async": "^2.5.0"
         },
         "optionalDependencies": {
           "chokidar": "^3.4.1",
           "watchpack-chokidar2": "^2.0.1"
         }
       },
   ...
   

   folders:

   ➜  3840 ls -hl ./node_modules | grep watchpack
   drwxrwxr-x  3 dmitriy dmitriy 4,0K мар 15 11:41 watchpack
   
   

2. there are dependencies with / in package name.
   e.g. @babel/plugin-transform-classes
   these dependencies start from @. We need to parse them properly.

[knqyf263]

Did you add a test for optional dependencies?

[knqyf263]

We can update the existing test case.

[DmitriyLewen]

Added optional deps to testcases

[knqyf263]

It should not happen, but I think we should check the length just in case.

Suggested change

	if strings.HasPrefix(paths[len(paths)-2], "@") {
	if len(paths) >= 2 && strings.HasPrefix(paths[len(paths)-2], "@") {

[DmitriyLewen]

Done