Upgrate to ynh9 from ynh2 broken

[curtosis]

Describe the bug

Running the app upgrade from the web admin or CLI fails with mysqldump: command not found.

Context

• Hardware: VPS bought online
• YunoHost version: 12.0.9
• I have access to my server: Through SSH | through the webadmin
• Are you in a special context or did you perform some particular tweaking on your YunoHost instance?: no
  • If yes, please explain:
• Using, or trying to install package version/branch: 2.5.4~ynh9
• If upgrading, current package version: 2.5.4~ynh2

Steps to reproduce

    sudo yunohost app upgrade wallabag2

Logs

logs here

[curtosis]

Obviously, upgrade was possible without a backup using -b but still thought it should be flagged here.

[lapineige]

DEBUG - + ynh_mysql_dump_db --database=wallabag2
INFO - Backing up the MySQL database...
DEBUG - + mysqldump --single-transaction --skip-dump-date --routines wallabag2
WARNING - /usr/share/yunohost/helpers.v1.d/mysql: line 154: mysqldump: command not found

Wtf is happening… 🤔