Update the pre-release version for preview 8.
Update the pre-release version for preview 8.

StephenBonikowsky/wcf,dotnet/wcf,imcarolwang/wcf,imcarolwang/wcf,dotnet/wcf,imcarolwang/wcf,mconnew/wcf,dotnet/wcf,mconnew/wcf,mconnew/wcf,StephenBonikowsky/wcf