[2.1]: Remove unused project capability from Microsoft.AspNetCore.App (#1237)

Removing this from .App in 2.1.3 because this was unused, and the capability is not actually supported by VS. This will be re-added in the future versions of .App when we land the VS integration for in-process hosting.

cref https://github.com/aspnet/IISIntegration/pull/969

src/Microsoft.AspNetCore.App/build/netcoreapp2.1/Microsoft.AspNetCore.App.props

@@ -11,11 +11,4 @@
     <_AspNetCoreAppSharedFxIsEnabled Condition=" '$(_AspNetCoreAppSharedFxIsEnabled)' == '' ">true</_AspNetCoreAppSharedFxIsEnabled>
   </PropertyGroup>
 
-  <!--
-    Capability that enables Visual Studio support for hosting Asp.Net Core applications in the IIS process
-  -->
-  <ItemGroup>
-    <ProjectCapability Include="AspNetInProcessHosting" />
-  </ItemGroup>
-
 </Project>