This bug is not fixed in plasma-discover 5.7.0-3.
See below:
Unpacking plasma-discover-common (5.7.0-3) over (5.6.5-1) ... dpkg: error processing archive /var/cache/apt/archives/plasma-discover-common_5.7.0-3_all.deb (--unpack): trying to overwrite '/usr/share/libdiscover/backends/knsplasmoids-backend.desktop', which is also in package plasma-discover-private 5.6.5-1 dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)