I'm getting the following issue:
==> Making package: ncurses5-compat-libs 6.0+20170902-1 (Sun 21 Jan 12:08:54 GMT 2018)
==> Checking runtime dependencies...
==> Checking buildtime dependencies...
==> Retrieving sources...
-> Downloading ncurses-6.0-20170902.tgz...
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 3244k 100 3244k 0 0 3244k 0 0:00:01 --:--:-- 0:00:01 3666k
-> Downloading ncurses-6.0-20170902.tgz.asc...
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 267 100 267 0 0 267 0 0:00:01 --:--:-- 0:00:01 1435
==> Validating source files with md5sums...
ncurses-6.0-20170902.tgz ... Passed
ncurses-6.0-20170902.tgz.asc ... Skipped
==> Verifying source file signatures with gpg...
ncurses-6.0-20170902.tgz ... FAILED (unknown public key 702353E0F7E48EDB)
==> ERROR: One or more PGP signatures could not be verified!