Nas backup restore fails if the backup repository mount options have a trailing space

### problem

Backup works because mount options are processed inside the shell script `nasbackup.sh` where trailing spaces are not a problem.

But restore (`LibvirtRestoreBackupCommandWrapper`) builds and runs mount in Java

```

if (StringUtils.isNotBlank(mountOptions)) {
mountCmd.add("-o");
mountCmd.add(mountOptions);
}
Script.executeCommand(mountCmd.toArray(new String[0]));

```
Script.executeCommand(String...) builds a ProcessBuilder argument list
mount receives the literal -o "vers=4.1 ". libmount splits options only on commas, so the trailing blank stays glued to the last option, and mount.nfs/the kernel rejects it as a malformed or unknown option ("an incorrect mount option was specified").

`WARN utils.script.Script (logid:435302bd) Process [445800] for command [sudo /usr/bin/mount -t nfs encountered the error: [mount.nfs: an incorrect mount option was specified for /usr/share/cloudstack-agent/tmp/csbackup...`

### versions

ACS 4.22.1

### The steps to reproduce the bug

1. Create a backup repository - specify mount options (`vers=4.1 `) with a trailing space
2. Create backup
3. Restore backup - it fails
...

### What to do about it?

Trim trailing whitespaces before using the mount options

LibvirtRestoreBackupCommandWrapper から始め、mountOptions が Script.executeCommand にどのように渡されるかを調べます。これを nasbackup.sh のシェル処理と比較します。末尾に空白を含むリポジトリオプションを使ってリストアを再現し、その後、リストアが成功することと、既存の mount コマンドの動作が変わらないことを確認します。

索引モデルが issue の本文から書いたものです。