test: make package json command check min files

[Techn1x]

Summary

See https://github.com/contentful/contentful.js/issues/1936

Description

I am hopeful that this can be used as a failing test (circle CI should run npm run build which will run these check commands and fail)

Screenshots (if appropriate):

[Techn1x]

@marcolink is this useful or should I close it?

[marcolink]

cc @mgoudy91

[Techn1x]

Would be great to see this fixed for a patch version. I did give it a go, but was only able to come up with the failing test.

[axe312ger]

This will be included in #2164

See: https://github.com/contentful/contentful.js/pull/2164/files#diff-7ae45ad102eab3b6d7e7896acd08c427a9b25b346470d7bc6507b6481575d519

[Techn1x]

Thankyou! Can confirm underlying issue resolved in 10.9.0+