Update WCF assemblies

[TianqiZhang]

Fixes #3132

Internal review URL

[mairaw]

@TianqiZhang any clue why the namespace system.servicemodel is not found for .NET Core 2.0, when the APIs underneath exist in 2.0?

see here an example: https://review.docs.microsoft.com/en-us/dotnet/api/system.servicemodel?view=netcore-2.0&branch=pr-en-us-3208

[mairaw]

@zhenlan do you wanna take a look at this PR and see if you see the APIs you'd expect to be added here? I already found an issue with the namespace page for System.ServiceModel.

[TianqiZhang]

@mairaw just checked, it should be an incremental build issue, this namespace has no content change, only moniker change, so it did not re-build for the PR. If we merge this PR and do a force build, the monikers on page will be fixed.

[mairaw]

Cool. I'll merge and test on master then. Thanks @TianqiZhang!

[zhenlan]

Looks good. Thank you @mairaw!