Algorand v.2.0.0 upgrade on Ubuntu installations

For installations that have performed the following installation instructions on Ubuntu (Debian package), I noticed that the node is not automatically upgraded from 1.x to 2.0.x

https://developer.algorand.org/docs/installing-ubuntu

Moreover, the apt-get update complains that it cannot find the GPG key.

Could you please add the key to the APT repository?

$ sudo apt-get update
Hit:1 http://mirror.hetzner.de/ubuntu/packages bionic InRelease
Get:2 http://mirror.hetzner.de/ubuntu/packages bionic-updates InRelease [88.7 kB]
Get:3 http://mirror.hetzner.de/ubuntu/packages bionic-backports InRelease [74.6 kB]
Get:4 http://mirror.hetzner.de/ubuntu/packages bionic-security InRelease [88.7 kB]
Hit:5 http://archive.ubuntu.com/ubuntu bionic InRelease
Get:6 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB]
Get:7 http://archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB]
Get:8 http://archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB]
Get:9 https://releases.algorand.com/deb stable InRelease [4,121 B]
Err:9 https://releases.algorand.com/deb stable InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 034BADABB3E375D4
Fetched 508 kB in 2s (264 kB/s)
Reading package lists... Done
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://releases.algorand.com/deb stable InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 034BADABB3E375D4
W: Failed to fetch https://releases.algorand.com/deb/dists/stable/InRelease  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 034BADABB3E375D4
W: Some index files failed to download. They have been ignored, or old ones used instead.

I did by manually downloading and installing it. go to https://releases.algorand.com and download .deb file and install it.