community/icingaweb2: no schema files for database

The community/icingaweb2 aport is missing the schmea files required for the backing database (https://github.com/Icinga/icingaweb2/tree/main/schema)

This is required for initial setup, but also leads to error messages in syslog:

Jan 14 04:34:50 d user.err icingaweb2[2552]: Failed to load pending migrations: UnexpectedValueException in /usr/share/webapps/icingaweb2/library/Icinga/Application/Hook/DbMigrationHook.php:306 with message: DirectoryIterator::__construct(/usr/share/webapps/icingaweb2/schema/mysql-upgrades): Failed to open directory: No such file or directory