Revert "Forgot to use configured user and group in binary recipe"

This reverts commit 554d91b4d18335db4418d28f4144af2b5c7e5347.

As the file is downloaded as root (I think at least), the configured
kafka user isn't able to extract it.
Test the right things in binary integration specs

Suppose I just copied the source integration specs
and then just didn't give a fuck. Oh well.