When update ghost cms in google cloud by bitnami. I face an error. look like. plz tell me
bitnami@officialrajjdeepsinghblog-vm:/home/radewala_2/apps/ghost/htdocs$ ghost update
    ✔ Checking system Node.js version
    ℹ Ensuring user is not logged in as ghost user [skipped]
    ℹ Checking if logged in user is directory owner [skipped]
    ✔ Checking current folder permissions
    ✔ Checking memory availability
    ✔ Checking free space
    ✔ Checking for available migrations
    ✖ Checking for latest Ghost version
    A CliError occurred.
    Message: Unable to update Ghost directly to v4.2.0. You must be on the latest v3.x to update across major versions.
    Help: Run "ghost update v3" to get the latest v3.x version, then run "ghost update" to get to v4.
    Debug Information:
    OS: Debian GNU/Linux, v10
    Node Version: v12.19.0
    Ghost Version: 3.40.2
    Ghost-CLI Version: 1.16.3
    Environment: production
    Command: 'ghost update'
    Additional log info available in: /home/bitnami/.ghost/logs/ghost-cli-debug-2021-04-11T08_49_03_257Z.log
    Try running ghost doctor to check your system for known issues.
    You can always refer to https://ghost.org/docs/ghost-cli/ for troubleshooting.