Action bound to abstract entity type is not present in OpenAPI output when using hidi to convert from CSDL

[gavinbarron]

Describe the bug
When generating the OpenAPI description for Microsoft Graph Beta the offboard and cancelOffboard routes are not generated for the protectionUnit entity

Reproduction Steps

In a PowerShell terminal with dotnet 9

dotnet tool install --global Microsoft.OpenApi.Hidi
git clone https://github.com/microsoftgraph/msgraph-metadata.git
hidi transform --csdl .\msgraph-metadata\clean_beta_metadata\cleanMetadata.xml --output .\beta-enhanced-restore.yaml --co  --version "3.0" --metadata-version "beta" --log-level Trace --format yaml --settings-path .\msgraph-metadata\conversion-settings\openapi.json

Alternatively if you clone the internal AD-AggregatorService-Workloads you can use a smaller source csdl file:

hidi transform --csdl .\AD-AggregatorService-Workloads\Workloads\Microsoft.EnhancedRestore\override\schema-Prod-beta.csdl --output .\beta-enhanced-restore-3.1.yaml --co  --version "3.1" --metadata-version "beta" --log-level Trace --format yaml

When opening the newly created beta-enhanced-restore.yaml you will not find a path that includes /cancelOffboard

When examining the smaller CSDL fragment for the Microsoft.EnhancedRestore I can see that the impacted Actions are all bound to an abstract type.

      <EntityType Name="protectionUnitBase" BaseType="microsoft.graph.entity" Abstract="true" >
        <Property Name="policyId" Type="Edm.String" />
        <Property Name="status" Type="self.protectionUnitStatus" />
        <Property Name="createdDateTime" Type="Edm.DateTimeOffset" />
        <Property Name="createdBy" Type="microsoft.graph.identitySet" />
        <Property Name="lastModifiedDateTime" Type="Edm.DateTimeOffset" />
        <Property Name="lastModifiedBy" Type="microsoft.graph.identitySet" />
        <Property Name="protectionSources" Type="self.protectionSource" Nullable="false" />
        <Property Name="error" Type="microsoft.graph.publicError" />
        <Property Name="offboardRequestedDateTime" Type="Edm.DateTimeOffset" />
      </EntityType>
      <EntityType Name="protectionRuleBase" BaseType="microsoft.graph.entity" Abstract="true" >
        <Property Name="status" Type="self.protectionRuleStatus" />
        <Property Name="createdDateTime" Type="Edm.DateTimeOffset" />
        <Property Name="createdBy" Type="microsoft.graph.identitySet" />
        <Property Name="lastModifiedDateTime" Type="Edm.DateTimeOffset" />
        <Property Name="lastModifiedBy" Type="microsoft.graph.identitySet" />
        <Property Name="error" Type="microsoft.graph.publicError" />
        <Property Name="isAutoApplyEnabled" Type="Edm.Boolean" />
      </EntityType>
      <Action Name="run" IsBound="true">
        <Parameter Name="bindingParameter" Type="self.protectionRuleBase"/>
        <ReturnType Type="self.protectionRuleBase"/>
      </Action>
      <Action Name="deleteAndUnprotect" IsBound="true" >
        <Parameter Name="bindingParameter" Type="self.protectionRuleBase"/>
        <ReturnType Type="self.protectionRuleBase"/>
      </Action>
    <Action Name="offboard" IsBound="true">
      <Parameter Name="bindingParameter" Type="self.protectionUnitBase"/>
      <ReturnType Type="self.protectionUnitBase"/>
    </Action>
    <Action Name="cancelOffboard" IsBound="true" >
      <Parameter Name="bindingParameter" Type="self.protectionUnitBase"/>
      <ReturnType Type="self.protectionUnitBase"/>
    </Action>

Expected behavior
the /offboard and /cancelOffboard request URIs are described in the OpenAPI output.

Additional context
This is an issue preventing the generated SDKs for Microsoft Graph from including these requests.