Remove RuntimeFrameworkVersion as this is given by the running version of PS anyway and .Net would upgrade automatically anyway if possible (PowerShell#1052)

* Remove RuntimeFrameworkVersion as this is given by the running version of PS anyway and .Net would upgrade automatically anyway if possible

* revert change of encoding

* Remove PackageTargetFallback, which was a leftover from .Net Core 1.0

Author: bergmeister

Rules/Rules.csproj

@@ -1,12 +1,10 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <VersionPrefix>1.17.1</VersionPrefix>
     <TargetFrameworks>netstandard2.0;net451</TargetFrameworks>
     <AssemblyName>Microsoft.Windows.PowerShell.ScriptAnalyzer.BuiltinRules</AssemblyName>
     <PackageId>Rules</PackageId>
-    <PackageTargetFallback Condition=" '$(TargetFramework)' == 'netstandard2.0' ">$(PackageTargetFallback)</PackageTargetFallback>
-    <RuntimeFrameworkVersion Condition=" '$(TargetFramework)' == 'netstandard2.0' ">1.0.4</RuntimeFrameworkVersion>
     <RootNamespace>Microsoft.Windows.PowerShell.ScriptAnalyzer</RootNamespace> <!-- Namespace needs to match Assembly name for ressource binding -->
   </PropertyGroup>