Add a simple script to set value of secrets to be the identical (#8091)

We have some unnecessary duplication of secrets, and the secret manager doesn't have a great way to handle this today.

scripts/set-duplicate-secret.ps1

@@ -0,0 +1,60 @@
+<#
+.SYNOPSIS
+Sets a secret in one vault to be the same as another. Temporary workaround for issues in secret
+layout. Assumes that the Keyvaults are in the same subscription and that the current context
+is set to that subscription.
+
+.PARAMETER SourceVaultName
+Vault where the source secret is located
+
+.PARAMETER SourceSecretName
+Name of source secret
+
+.PARAMETER DestinationVaultName
+Vault where the destination secret is located
+
+.PARAMETER DestinationSecretName
+Name of destination secret. If not specified, the source secret name is used.
+
+#>
+
+param (
+    [Parameter(Mandatory=$true)]
+    [string]$SourceVaultName,
+    [Parameter(Mandatory=$true)]
+    [string]$SourceSecretName,
+    [Parameter(Mandatory=$true)]
+    [string]$DestinationVaultName,
+    [string]$DestinationSecretName
+)
+
+if (!$DestinationSecretName) {
+    $DestinationSecretName = $SourceSecretName
+}
+
+$sourceSecretInfo = Get-AzKeyVaultSecret -VaultName $SourceVaultName -Name $SourceSecretName
+$destinationSecretInfo = Get-AzKeyVaultSecret -VaultName $DestinationVaultName -Name $DestinationSecretName
+
+if (!$sourceSecretInfo) {
+    Write-Error "Could not find source secret '$SourceSecretName' in '$SourceVaultName'"
+    return
+}
+
+if (!$destinationSecretInfo) {
+    Write-Error "Could not find destination secret '$DestinationSecretName' in '$DestinationVaultName'"
+    return
+}
+
+if ($($sourceSecretInfo.SecretValue | ConvertFrom-SecureString -AsPlainText) -eq $($destinationSecretInfo.SecretValue | ConvertFrom-SecureString -AsPlainText)) {
+    Write-Host "Secrets are already the same, not updating."
+    return
+}
+
+$newDestinationSecret = Set-AzKeyVaultSecret -VaultName $DestinationVaultName -Name $DestinationSecretName -SecretValue $sourceSecretInfo.SecretValue -Expires $sourceSecretInfo.Expires -Tag $sourceSecretInfo.Tags -ContentType $sourceSecretInfo.ContextType
+
+if ($($sourceSecretInfo.SecretValue | ConvertFrom-SecureString -AsPlainText) -ne $($newDestinationSecret.SecretValue | ConvertFrom-SecureString -AsPlainText)) {
+    Write-Error "Destination secret was not correctly updated"
+    return
+} else {
+    Write-Host "Destination secret '$DestinationSecretName' in '$DestinationVaultName' is now the same as '$SourceSecretName' in '$SourceVaultName'"
+}