Fix System.Data.SqlClient dependency version on compat pack

[safern]

Fixes: #55952

We should not treat System.Data.SqlClient as an indexed dependency on the compat pack as it is coming from an external repository, so every time a new version is released if we update the dependency version and don't update the packageIndex our infrastructure would treat it as a prerelease version rather than stable.

[ghost]

Tagging subscribers to this area: @Anipik, @safern, @ViktorHofer
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Fixes: #55952

We should not treat System.Data.SqlClient as an indexed dependency on the compat pack as it is coming from an external repository, so every time a new version is released if we update the dependency version and don't update the packageIndex our infrastructure would treat it as a prerelease version rather than stable.

Author:	safern
Assignees:	-
Labels:	area-Infrastructure-libraries
Milestone:	-

[safern]

Failures are unrelated.

[safern]

/backport to release/6.0-preview7

[github-actions]

Started backporting to release/6.0-preview7: https://github.com/dotnet/runtime/actions/runs/1050047702

[ViktorHofer]

Thanks for the fix Santi 👍 One question so that I better understand the fallout:

We should not treat System.Data.SqlClient as an indexed dependency on the compat pack as it is coming from an external repository, so every time a new version is released if we update the dependency version and don't update the packageIndex our infrastructure would treat it as a prerelease version rather than stable.

I'm not sure if that's correct. System.Data.SqlClient lives in corefx which we don't treat as an external repository (do we?). Microsoft.Data.SqlClient is the new package which lives in https://github.com/dotnet/SqlClient but which we don't depend on in the Windows.Compatibility package.

Aside from servicing fixes, AFAIK the System.Data.SqlClient package should never change again. Does that impact the fix applied here?

[safern]

I'm not sure if that's correct. System.Data.SqlClient lives in corefx which we don't treat as an external repository (do we?). Microsoft.Data.SqlClient is the new package which lives in https://github.com/dotnet/SqlClient but which we don't depend on in the Windows.Compatibility package.

IMHO it shouldn't be a decision based on what repo the package is built, I think we should only index dependencies for packages that are still live built at the same branch as the compat pack. The reason for that is because an indexed dependency means that is a stable package is not listed we will produce a version with the prerelease label that we are producing on that current build based on date and time of the build being produce. So I think that is what leads to this kind of bugs, now we have testing of this package going forward so it doesn't matter much as we would catch it as part of the build, but since packages that are no longer built on the current branch should not be indexed and should just be pinned as those packages will never have a package with version with the prerelease label produced on that branch.