Add partial checkout support to build CI step

[pakrym]

I've switched all other CI steps to partial checkout with session record filtering with great results (5x checkout time improvement).

The build step is the last major one left. It's blocked by the lack of sparse checkout repo support in SourceLink (dotnet/sourcelink#771). SourceLink is a tool we use to embed source control information (repository/commit/etc.) into resulting DLLs to help debugging.

I have a fix for SourceLink in dotnet/sourcelink#772

I was able to get sparse checkout working in all steps except build because those don't produce DLLs that we ship to customers and disabling SourceLink won't affect anyone (https://github.com/Azure/azure-sdk-for-net/search?q=EnableSourceLink&type=).

[pakrym]

PRs that added support to other steps:
#26001
#25983
#26001

[github-actions]

Hi @pakrym, we deeply appreciate your input into this project. Regrettably, this issue has remained inactive for over 2 years, leading us to the decision to close it. We've implemented this policy to maintain the relevance of our issue queue and facilitate easier navigation for new contributors. If you still believe this topic requires attention, please feel free to create a new issue, referencing this one. Thank you for your understanding and ongoing support.

[github-actions]

Hi @pakrym, we deeply appreciate your input into this project. Regrettably, this issue has remained inactive for over 2 years, leading us to the decision to close it. We've implemented this policy to maintain the relevance of our issue queue and facilitate easier navigation for new contributors. If you still believe this topic requires attention, please feel free to create a new issue, referencing this one. Thank you for your understanding and ongoing support.