Remove version overrides in Azure.AI.Projects

[howieleung]

There are two local version overrides in sdk/ai/Azure.AI.Projects/tests/Azure.AI.Projects.Tests.csproj which need to be removed after the next stable versions of Azure.Search.Documents and Azure.AI.OpenAI are released with a move to the 8.x line of BCL dependencies. Once released to GA, the global references to them can be bumped and the local overrides removed.

[github-actions]

Thanks for the feedback! We are routing this to the appropriate team for follow-up. cc @dargilco @jhakulin @nick863.

[howieleung]

Azure.Search.Documents is done. but Azure.AI.OpenAI still has 2.2.0 on beta. Need to wait for 2.2.0 GA.