remove: remove utils/deep-get

This commit removes `@stdlib/utils/deep-get` in favor of
`@stdlib/object/deep-get`.

BREAKING CHANGE: remove `utils/deep-get`

To migrate, users should update their require/import paths to use
`@stdlib/object/deep-get` which provides the same API and implementation.

Ref: #8755

Author: Neerajpathak07