I cannot authenticate with packagedb-cli-2.11-1.fc23. I can with packagedb-cli-2.10-2.fc23. It prints error "ServerError(https://admin.fedoraproject.org/pkgdb/api/package/rpms/perl-Time-HiRes/monitor/nobuild, 200, Error returned from json module while processing https://admin.fedoraproject.org/pkgdb/api/package/rpms/perl-Time-HiRes/monitor/nobuild: Expecting value: line 2 column 1 (char 1)" and then an "OpenID transaction in progress" HTML page.
This not a bug in the miniz-devel package. Every Epackage is the EPEL repozitory is available in x86_64 and i686 variant. The issue is there is no glibc-headers.i686 package to fulfill the dependencies on glibc header files. I will correct change to dependency from glibc-headers to gcc as conform C guidelines, but it will not fix the issue for you. The real fix would be to exlude the miniz-devel.i686 from x86_64 EPEL repozitory. But I worry EPEL does not support it. This is a release engineering deficiency in multilib handling when composing repositories. Simply do not install miniz-devel.i686 on x86_64 machine. Install miniz-devel instead.