Olivier Lemasle 72f6612971
server: Increase max length for VMInstanceVO.backupVolumes (#4967)
The default length is 255, which caused a truncation of data if
the JSON object representing the backup volumes is too big.
It caused errors when backups were made on VMs with 3 volumes
or more.

`vm_instance.backup_volumes` has the type TEXT, which has a
maximal length of 65535 characters.

Fixes #4965
2021-04-30 11:57:56 +05:30
..