fix(cache): cache add

[milaninfy]

This will fix the npm cache add to cache package with same header as it's used in npm install by adding fullMetadata: true while caching.

npm install requests package with fullMetadata flag while npm cache add does not pass that argument and results in request with corgi document header ( accept: 'application/vnd.npm.install-v1+json; q=1.0, application/json; q=0.8, */* ) than full header (accept: 'application/json).

References

Closes #7465