chore: delete deploy-update-ssh-account-keys (#3549)

`deploy-update-ssh-account-keys` updates the HostOS ssh backup and
readonly account keys if `/opt/ic/share/authorized_keys/` is populated
with new account keys. This code is not used. This PR removes it.

ic-os/components/hostos.bzl

@@ -89,8 +89,6 @@ component_files = {
     Label("ssh/generate-host-ssh-keys/generate-host-ssh-keys.service"): "/etc/systemd/system/generate-host-ssh-keys.service",
     Label("ssh/setup-ssh-user-keys/setup-ssh-user-keys.sh"): "/opt/ic/bin/setup-ssh-user-keys.sh",
     Label("ssh/setup-ssh-user-keys/setup-ssh-user-keys.service"): "/etc/systemd/system/setup-ssh-user-keys.service",
-    Label("ssh/deploy-updated-ssh-account-keys/deploy-updated-ssh-account-keys.sh"): "/opt/ic/bin/deploy-updated-ssh-account-keys.sh",
-    Label("ssh/deploy-updated-ssh-account-keys/deploy-updated-ssh-account-keys.service"): "/etc/systemd/system/deploy-updated-ssh-account-keys.service",
 
     # upgrade
     Label("upgrade/manageboot/manageboot.sh"): "/opt/ic/bin/manageboot.sh",

ic-os/guestos/docs/Boot.adoc

@@ -170,15 +170,6 @@ USB stick" attached to the VM that contains a tar file with initial configuratio
 for parts of the system. Required files in the +config+ partition as well as 
 payload store are created.
 
-== Deploy updated ssh account keys
-
-Service: +deploy-updated-ssh-account-keys.service+, +deploy-updated-ssh-account-keys.sh+.
-Depends on +bootstrap-ic-node.service+, runs before +setup-ssh-account-keys.service+.
-
-Changes the keys held in the +config+ partition for the +backup+ and +readonly+ user. This
-is a work-around due to not having a key management solution that updated keys are
-deployed via system upgrades.
-
 == Set up ssh user keys
 
 Service: +setup-ssh-user-keys.services+, script +/opt/ic/bin/setup-ssh-user-keys.sh+.