Customer feedback | az dataprotection backup-instance update | can you show an example of {backup_configuration}?

### Engineering request

1. Fix the typo error in the existing sample
2. Add an example of the syntax you are expecting in `{backup_configuration}` for the `--container-blob-list` parameter, or how to generate the configuration. The `long-summary` property of the parameter would be a good place for this.

### Describe the bug

From Learn Customer Feedback, a customer is looking for an example value for **{backup_configuration}**, but upon closer inspection, the example is using a parameter that isn't in the list of availabile parameters.

### Feedback category
1. Missing example
2. Parameter used is not in list

### Doc link
https://learn.microsoft.com/en-us/cli/azure/dataprotection/backup-instance?view=azure-cli-latest#az-dataprotection-backup-instance-update

### Customer feedback
"
az dataprotection backup-instance update --backup-instance-name MyDisk1 --vaulted-blob-container-list {backup_configuration} -g MyResourceGroup --vault-name MyVault

can you show an example of backup_configuration?
"

### Screen print

### Related command

az dataprotection backup-instance update