udisks2 prompts for user password on recent Fedora

[npmccallum]

I don't know what broke this. But we should fix it.

@martinezjavier FYI

[Plailect]

I am using the KDE spin of Fedora 29 and the udisks2 unlocker does not work at all. If I run /usr/libexec/clevis-luks-udisks2 manually it produces no output and seemingly hangs forever. The suid bit is indeed set on the binary.