Can't create backup with xtrabackup 8.0.13

User impact:

Backup action fails with the error if target node has installed xtrabackup version 8.0.13.

Steps to reproduce:

1. Add mysql instance to pmm
2. Install xtrabackup 8.0.13 on the node with DB
3. Start backup form PMM UI

Actual result:

There is an error pop-up on the UI with `Internal Server Error` text

Expected result:

Backup finished successfully

Workaround:

Before starting backup PMM checks required tools versions for compatibility. For xbcloud it uses `xbcloud --version` command, however that flag was added since xtrabackup 8.0.23.

So we have some options:

1. Do not support xtrabackup < 8.0.23
2. For old xtrabackup versions version is printed in the top of `–help` command

Also we should provide better error on the UI for similar errors.

Details: