repository configuration tool - for ubuntu/debian - wrong GPG key

root@:~# sudo apt-key adv --recv-keys --keyserver hkp://keyserver.ubuntu.com:80 0xcbcb082a1bb943db

Executing: /tmp/tmp.bj4twk9UCy/gpg.1.sh --recv-keys

--keyserver

hkp://keyserver.ubuntu.com:80

0xcbcb082a1bb943db

gpg: requesting key 1BB943DB from hkp server keyserver.ubuntu.com

gpg: key 1BB943DB: public key "MariaDB Package Signing Key <package-signing-key@mariadb.org>" imported

gpg: Total number processed: 1

gpg:               imported: 1

root@:~# apt-get update

Get:1 http://ftp.osuosl.org/pub/mariadb/repo/10.1/ubuntu xenial InRelease [3,874 B]

Ign:1 http://ftp.osuosl.org/pub/mariadb/repo/10.1/ubuntu xenial InRelease

Hit:2 http://archive.ubuntu.com/ubuntu xenial InRelease

Hit:3 http://ports.ubuntu.com/ubuntu-ports xenial InRelease

Hit:4 http://archive.ubuntu.com/ubuntu xenial-updates InRelease

Hit:5 http://ports.ubuntu.com/ubuntu-ports xenial-updates InRelease

Hit:6 http://archive.ubuntu.com/ubuntu xenial-backports InRelease

Hit:7 http://ports.ubuntu.com/ubuntu-ports xenial-backports InRelease

Hit:8 http://ports.ubuntu.com/ubuntu-ports xenial-security InRelease

Get:9 ftp://ftp.unicamp.br/pub/linuxpatch/toolchain/at/ubuntu utopic InRelease [4,022 B]

Fetched 7,896 B in 2s (3,408 B/s)

Reading package lists... Done

W: GPG error: http://ftp.osuosl.org/pub/mariadb/repo/10.1/ubuntu xenial InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY F1656F24C74CD1D8

W: The repository 'http://ftp.osuosl.org/pub/mariadb/repo/10.1/ubuntu xenial InRelease' is not signed.

N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.