Downgrade S.T.J to 8.0.0

[ViktorHofer]

This is necessary so that dotnet/sdk can also downgrade STJ back to 8.0.0. I had to pick 8.0.0 as 8.0.3 isn't available on SBRP.
We can't update to 8.0.4 yet as we don't yet have a VS with S.T.J/8.0.0.4 binding redirects for msbuild on .NET Framework.

This is needed for 9.0 P7. Apparently this doesn't need to be backported as this repo doesn't branch per preview.

cc @rainersigwald @marcpopMSFT @Forgind

[ViktorHofer]

Argh, the PR got merged because the pipeline is not marked as required. Will submit a fix. Need to get the package into SBRP first.

[marcpopMSFT]

To summarize the issue, the SDK inserts two components (template locator and the msbuild sdk resolver) into VS. Those components depend on STJ, compile for .NET framework, run in the VS process, and use the STJ from VS. As such, we have to compile against whatever version VS is currently shipping (or older).

This was an issue earlier this year where we updated these two assemblies to depend on version 8.0.2 and then VS would error when creating an aspire project as it couldn't load the template locator package.

Here's the PR where it was fixed previously after we identified the VS block during testing:
dotnet/sdk#39901

[marcpopMSFT]

(and if non-obvious, those two assemblies depend on the releases assembly so this repo has to align on versions with those two sdk assemblies)