Build Analysis and Helix Queue Insights checks block PRs without AzDO pipelines

This PR only has a markdown change and did not kick off an AzDO run. The checks run, but since there's no AzDO build, the checks just sit there in a waiting state. https://github.com/dotnet/runtime/pull/112885 (also see screenshot below)


Unsure if related, but a change was made to the status of the check recently: https://dnceng.visualstudio.com/internal/_git/dotnet-helix-service/pullrequest/49015

Discussion here: https://teams.microsoft.com/l/message/19:afba3d1545dd45d7b79f34c1821f6055@thread.skype/1745408179841?tenantId=72f988bf-86f1-41af-91ab-2d7cd011db47&groupId=4d73664c-9f2f-450d-82a5-c2f02756606d&parentMessageId=1745408179841&teamName=.NET%20Core%20Eng%20Services%20Partners&channelName=First%20Responders&createdTime=1745408179841

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*Migrated from AzDO work item [#8534](https://dev.azure.com/dnceng/internal/_workitems/edit/8534)*

Start with the markdown-only example in dotnet/runtime#112885 and compare the check status behavior with the recent dotnet-helix-service PR #49015. Reproduce a PR that does not trigger an AzDO pipeline and inspect the Build Analysis and Helix Queue Insights check entry points. Done means these checks no longer remain waiting when no AzDO build exists.

Written by the indexing model from the issue text.