Convert all Repository entries to RepositoryV2

[directhex]

Using RepositoryV2 should decrease build times, improve reliability, and help eliminate "hey I thought I was opted in for source.dot.net, why is my repo missing? (e.g. https://github.com/dotnet/source-indexer/issues/138)"

• [x] winforms https://github.com/dotnet/winforms/pull/11667
• [ ] iot runs on dotnet not dnceng, didn't know this existed until today, likely not permissible to ingest data from here
• [ ] msbuild runs on devdiv not dnceng, needs coordination in setting up a new service connection for artifact upload
• [ ] performance not clear which projects to include, discuss w/ repo owner
• [ ] sdk https://github.com/dotnet/sdk/pull/42132

[ericstj]

Maybe we could pull data from public artifacts if repos can't push to our blob storage. -- could be something to try for MSBuild or IOT.