This key is not certified with a trusted signature

[finrod2002]

Probably not a big deal and maybe I did something wrong, but if I run the recommended PGP signature verification

curl -sSL https://github.com/shyiko/kubetpl/releases/download/0.9.0/kubetpl-0.9.0-$(
    bash -c '[[ $OSTYPE == darwin* ]] && echo darwin || echo linux'
  )-amd64.asc -o kubetpl.asc
curl -sS https://keybase.io/shyiko/pgp_keys.asc | gpg --import
gpg --verify kubetpl.asc /usr/local/bin/kubetpl

I get the following output

gpg: Signature made Thu Jan 17 07:42:35 2019 STD
gpg:                using RSA key 160A7A9CF46221A56B06AD64461A804F2609FD89
gpg: Good signature from "Stanley Shyiko <[email protected]>" [unknown]
gpg: WARNING: This key is not certified with a trusted signature!
gpg:          There is no indication that the signature belongs to the owner.
Primary key fingerprint: 160A 7A9C F462 21A5 6B06  AD64 461A 804F 2609 FD89

So the key doesn't seem to be certified with a trusted signature.