[Bug] Upgrade to 2.71.1 breaks API generation

[martintmk]

Describe the bug
In Polly we upgraded the DocFx to version 2.71.1 from version 2.71.0:
App-vNext/Polly#1705

This caused the following deployment change:
App-vNext/Polly@99fd1b3#diff-b6331d69d43f82568b37f3431243dbe7c3bfc9b656ee87eed347874c5a427032

As a result, our API docs are no longer rendering:
https://www.pollydocs.org/api/

To Reproduce
Steps to reproduce the behavior:

1. Checkout Polly codebase
2. Go to /docs folder and run dotnet docfx --serve

Expected behavior
The API docs should be build.

Context (please complete the following information):

• OS: Windows
• Docfx version: 2.71.1

[yufeih]

Is it the same reason as #9311? https://github.com/App-vNext/Polly/blob/main/docs/docfx.json#L6C12-L6C15

[martintmk]

Yes, this one is duplicate of #9311.