確認

$ cat /etc/os-release
PRETTY_NAME="Ubuntu 22.04.5 LTS"
NAME="Ubuntu"
VERSION_ID="22.04"
VERSION="22.04.5 LTS (Jammy Jellyfish)"
VERSION_CODENAME=jammy
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
UBUNTU_CODENAME=jammy

パッケージをUpgrade

$ sudo apt update
<snip...>
$ sudo apt upgrade
<snip...>
$ sudo apt autoremove
<snip...>

一度Windowsから、シャットダウン

C:\Users\xxx> wsl --shutdown

~$ sudo do-release-upgrade -c
Checking for a new Ubuntu release
In /etc/update-manager/release-upgrades Prompt
is set to never so upgrading is not possible.

おっと！
アップグレードのチェック機能が「無効（never）」だって
/etc/update-manager/release-upgrades を修正

Prompt=never
   ⇓
Prompt=lts