`BackupResourceVaultConfigs_Update` of `Microsoft.RecoveryServices@2021-12-01` has a delay some times

We call [`BackupResourceVaultConfigs_Update`](https://github.com/Azure/azure-rest-api-specs/blob/main/specification/recoveryservicesbackup/resource-manager/Microsoft.RecoveryServices/stable/2021-12-01/bms.json#L657) to update recovery vaults.

We passed `softDeleteFeatureState` with `Disabled`, and the request returned with operation success. Then we called [`BackupResourceVaultConfigs_Get`](https://github.com/Azure/azure-rest-api-specs/blob/main/specification/recoveryservicesbackup/resource-manager/Microsoft.RecoveryServices/stable/2021-12-01/bms.json#L614), it returned with the old value (`softDeleteFeatureState` = `Enabled`) sometime. We have to keep calling "GET" for times then we get the correct value.

Start with the linked bms.json definitions for BackupResourceVaultConfigs_Update at line 657 and BackupResourceVaultConfigs_Get at line 614. Reproduce the update-then-get sequence using softDeleteFeatureState=Disabled and determine whether the repository contains a specification change to make; the issue currently provides no code location or completion criterion.

Written by the indexing model from the issue text.