Add back missing parameter completion functionality (#25654)

Author: mentat9

src/Resources/Policy.Autorest/custom/New-AzPolicyAssignment.ps1

@@ -113,6 +113,7 @@ param(
     [Parameter(ValueFromPipelineByPropertyName)]
     [ValidateNotNullOrEmpty()]
     [ValidateSet('Default', 'DoNotEnforce')]
+    [Microsoft.Azure.PowerShell.Cmdlets.Policy.PSArgumentCompleterAttribute('Default', 'DoNotEnforce')]
     [Microsoft.Azure.PowerShell.Cmdlets.Policy.Category('Body')]
     [System.String]
     # The policy assignment enforcement mode.
@@ -121,6 +122,7 @@ param(
 
     [Parameter()]
     [ValidateSet('None', 'SystemAssigned', 'UserAssigned')]
+    [Microsoft.Azure.PowerShell.Cmdlets.Policy.PSArgumentCompleterAttribute('None', 'SystemAssigned', 'UserAssigned')]
     [Microsoft.Azure.PowerShell.Cmdlets.Policy.Category('Body')]
     [System.String]
     # The identity type.

src/Resources/Policy.Autorest/custom/New-AzPolicyExemption.ps1

@@ -52,6 +52,7 @@ param(
 
     [Parameter(ValueFromPipelineByPropertyName)]
     [ValidateSet('Default', 'DoNotValidate')]
+    [Microsoft.Azure.PowerShell.Cmdlets.Policy.PSArgumentCompleterAttribute('Default', 'DoNotValidate')]
     [Microsoft.Azure.PowerShell.Cmdlets.Policy.Category('Body')]
     [System.String]
     # Whether to validate the exemption is at or under the assignment scope.
@@ -71,6 +72,7 @@ param(
 
     [Parameter(ParameterSetName='Default', Mandatory, ValueFromPipelineByPropertyName)]
     [ValidateSet('Waiver', 'Mitigated')]
+    [Microsoft.Azure.PowerShell.Cmdlets.Policy.PSArgumentCompleterAttribute('Waiver', 'Mitigated')]
     [Microsoft.Azure.PowerShell.Cmdlets.Policy.Category('Path')]
     [System.String]
     # The policy exemption category

src/Resources/Policy.Autorest/custom/Update-AzPolicyAssignment.ps1

@@ -124,6 +124,7 @@ param(
     [Parameter(ValueFromPipelineByPropertyName)]
     [ValidateNotNullOrEmpty()]
     [ValidateSet('Default', 'DoNotEnforce')]
+    [Microsoft.Azure.PowerShell.Cmdlets.Policy.PSArgumentCompleterAttribute('Default', 'DoNotEnforce')]
     [Microsoft.Azure.PowerShell.Cmdlets.Policy.Category('Body')]
     [System.String]
     # The policy assignment enforcement mode.
@@ -132,6 +133,7 @@ param(
 
     [Parameter()]
     [ValidateSet('None', 'SystemAssigned', 'UserAssigned')]
+    [Microsoft.Azure.PowerShell.Cmdlets.Policy.PSArgumentCompleterAttribute('None', 'SystemAssigned', 'UserAssigned')]
     [Microsoft.Azure.PowerShell.Cmdlets.Policy.Category('Body')]
     [System.String]
     # The identity type.

src/Resources/Policy.Autorest/custom/Update-AzPolicyExemption.ps1

@@ -74,6 +74,7 @@ param(
 
     [Parameter(ValueFromPipelineByPropertyName)]
     [ValidateSet('Waiver', 'Mitigated')]
+    [Microsoft.Azure.PowerShell.Cmdlets.Policy.PSArgumentCompleterAttribute('Waiver', 'Mitigated')]
     [Microsoft.Azure.PowerShell.Cmdlets.Policy.Category('Path')]
     [System.String]
     # The policy exemption category
@@ -115,6 +116,7 @@ param(
 
     [Parameter()]
     [ValidateSet('Default', 'DoNotValidate')]
+    [Microsoft.Azure.PowerShell.Cmdlets.Policy.PSArgumentCompleterAttribute('Default', 'DoNotValidate')]
     [Microsoft.Azure.PowerShell.Cmdlets.Policy.Category('Body')]
     [System.String]
     # The option whether validate the exemption is at or under the assignment scope.