Revert "upgrade projects with build.sql 2.1 (#2584)"

[ssreerama]

This reverts commit a8a5714.

Pull Request Template – SQL Tools Service

Description

Microsoft.Build.sql Nuget has issue with downloading from Nuget.org after the indexing issue resolved on nuget.org. This would not help using the 2.1.0 versions.

Code Changes Checklist

• New or updated unit tests added
• All existing tests pass (dotnet test)
• Code follows contributing guidelines
• Logging/telemetry updated if relevant
• No protocol or behavioral regressions

Reviewers: Please read our reviewer guidelines

[github-actions]

As part of updating the dependencies in Packages.props we require that any PRs opened also verify that
they've done the following checks.

Please respond to this comment verifying that you've done the appropriate validation (or explain why it's not necessary) before merging in the PR

• Built and tested the change locally to validate that the update doesn't cause any regressions and fixes the issues intended
• Tested changes on all major platforms
  • Windows
  • Linux
  • Mac
• Check the source repo for any open issues with the release being updated to (if available)

[ssreerama]

Testing the Build.Sql 2.1 Nuget (it just got fixed).

if is really got fixed, then we can abandon this PR

[ssreerama]

No issue with build.sql