Azure.Core.Expressions.DataFactory should be properly annotated for AOT #55162
Description
As of #53752 partially trimming libraries and baselining warnings is no longer an allowed path. This library was allowed as an exception for backwards compat.
The warnings in https://github.com/Azure/azure-sdk-for-net/blob/main/sdk/core/Azure.Core.Expressions.DataFactory/tests/compatibility/ExpectedAotWarnings.txt should be resolved and the expected warnings txt file removed.