main/openssh: (ssh-copy-id) expr: warning: '^ERROR: ': using '^' as the first character

When using ssh-copy-id, it leaks some error in the middle about a non-portable regular expression

> /usr/bin/ssh-copy-id -i destiny.whynothugo.nl.pub hugo@192.168.21.151 
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "destiny.whynothugo.nl.pub"
The authenticity of host '192.168.21.151 (192.168.21.151)' can't be established.
ED25519 key fingerprint is SHA256:vg2LPmwqz+3wGP266EqB7i76/qaeF4bKnEnRrTNHeI0.
This key is not known by any other names.
Are you sure you want to continue connecting (yes/no/[fingerprint])? fingerprint
Please type 'yes', 'no' or the fingerprint: yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
expr: warning: '^ERROR: ': using '^' as the first character
of a basic regular expression is not portable; it is ignored
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
no such identity: /home/hugo/.ssh/keys/192.168.21.151: No such file or directory
hugo@192.168.21.151's password: 

The executable in question here is a shell script. Line 237 seems to contain the regex in question:

if expr "$NEW_IDS" : "^ERROR: " >/dev/null ; then

Not entirely sure if we want to patch this locally. It might be best to report this upstream.