Ticket created from upstream issue: https://github.com/389ds/389-ds-base/issues/7027

*Issue Description*
leaked_handle: Handle variable "fd" going out of scope leaks the handle.

A file is opened using open() and then wrapped in a zlib gzFile with gzdopen(). If gzdopen() fails, it never takes ownership of the fd, so it remains open. Ensure fd is explicitly closed when gzdopen() returns NULL.