Remove KoreBuild-isms from project templates (dotnet/aspnetcore#667)

Removing MSBuild properties and items are for our build infrastructure, not for customers.

Commit migrated from dotnet/aspnetcore@af616d9b99

src/Microsoft.DotNet.Web.Spa.ProjectTemplates/Angular-CSharp.csproj.in

@@ -11,8 +11,6 @@
 
     <!-- Set this to true if you enable server-side prerendering -->
     <BuildServerSideRenderer>false</BuildServerSideRenderer>
-    <!-- aspnet/BuildTools#662 Don't police what version of NetCoreApp we use -->
-    <NETCoreAppMaximumVersion>99.9</NETCoreAppMaximumVersion>
   </PropertyGroup>
 
   <ItemGroup Condition="'$(TargetFrameworkOverride)' == ''">

src/Microsoft.DotNet.Web.Spa.ProjectTemplates/React-CSharp.csproj.in

@@ -8,8 +8,6 @@
     <IsPackable>false</IsPackable>
     <SpaRoot>ClientApp\</SpaRoot>
     <DefaultItemExcludes>$(DefaultItemExcludes);$(SpaRoot)node_modules\**</DefaultItemExcludes>
-    <!-- aspnet/BuildTools#662 Don't police what version of NetCoreApp we use -->
-    <NETCoreAppMaximumVersion>99.9</NETCoreAppMaximumVersion>
   </PropertyGroup>
 
   <ItemGroup Condition="'$(TargetFrameworkOverride)' == ''">

src/Microsoft.DotNet.Web.Spa.ProjectTemplates/ReactRedux-CSharp.csproj.in

@@ -8,8 +8,6 @@
     <IsPackable>false</IsPackable>
     <SpaRoot>ClientApp\</SpaRoot>
     <DefaultItemExcludes>$(DefaultItemExcludes);$(SpaRoot)node_modules\**</DefaultItemExcludes>
-    <!-- aspnet/BuildTools#662 Don't police what version of NetCoreApp we use -->
-    <NETCoreAppMaximumVersion>99.9</NETCoreAppMaximumVersion>
   </PropertyGroup>
 
   <ItemGroup Condition="'$(TargetFrameworkOverride)' == ''">