Fix concurrent tool restore and version range error

[JL03-Yue]

Customer Impact

In .NET 8 we made a breaking change that changes the current .NET tool installation mechanism from restore a local temporary project to downloading the .NET tool from NuGet. This change was introduced because this previous mechanism has number of side effects, often show up as flaky restore errors because MSBuild concepts like Directory.Build.props, or other heirarchical notions, pollute the restore.

The change, however, affect the behavior in tool restore. For one, the change in tool install affect the parallel tool restore as it might read multiple too info into the same config file. For another, the change of getting tool's version tries to read from a property .originalString that might not exist.

The intended way to fix this is to make the parallel tool restore sequential, and to get rid of reading the .originalString property. To make the tool restore sequential, instead of using AsParallel() in the code, the updated code uses AsEnumerate() to reduce the chance of error. For version, this pull request adds a condition to check if the versionRange passed in is null and set it to a default value.
Both changes are validated by tests.

Testing
Existing unit tests passed without changes. New tested are added to validate tool restore returns the correct version, and tool restore is able to restore multiple tools. The new testing scenarios pass with changes in the pull request.

Risk
Low. This change resolves some errors caused by breaking change by add conditions to set the versionRange and make parallel tool restore sequential, without adding complexity to the behavior.

Current unit tests passed without changes, and new tests are added to validate the change. Even though making parallel tool restore sequential might reduce the speed of tool restore, this is a validate approach because it reduces the risk of issues from concurrent restoration.

Original description
Referred to Add known issue for .NET tool restore in .NET 8 RC2

[JL03-Yue]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[dsplaisted]

Looks great!

[wtgodbe]

Approved over email

[JL03-Yue]

fixes #35999