Pin NETStandard.Library.Ref (#16710)

Fixup sha for v3.0.0

Author: mmitche

eng/Version.Details.xml

@@ -397,9 +397,9 @@
       <Uri>https://github.com/dotnet/core-setup</Uri>
       <Sha>4950751278293d59898be799c0115e0ad895747e</Sha>
     </Dependency>
-    <Dependency Name="NETStandard.Library.Ref" Version="2.1.0-preview3.19530.5" CoherentParentDependency="Microsoft.Extensions.Logging">
+    <Dependency Name="NETStandard.Library.Ref" Version="2.1.0" Pinned="true">
       <Uri>https://github.com/dotnet/core-setup</Uri>
-      <Sha>4950751278293d59898be799c0115e0ad895747e</Sha>
+      <Sha>7d57652f33493fa022125b7f63aad0d70c52d810</Sha>
     </Dependency>
   </ProductDependencies>
   <ToolsetDependencies>

eng/Versions.props

@@ -69,7 +69,7 @@
     <MicrosoftExtensionsDependencyModelPackageVersion>3.1.0-preview3.19530.5</MicrosoftExtensionsDependencyModelPackageVersion>
     <MicrosoftNETCoreAppRefPackageVersion>3.1.0-preview3.19530.5</MicrosoftNETCoreAppRefPackageVersion>
     <MicrosoftNETCoreAppRuntimewinx64PackageVersion>3.1.0-preview3.19530.5</MicrosoftNETCoreAppRuntimewinx64PackageVersion>
-    <NETStandardLibraryRefPackageVersion>2.1.0-preview3.19530.5</NETStandardLibraryRefPackageVersion>
+    <NETStandardLibraryRefPackageVersion>2.1.0</NETStandardLibraryRefPackageVersion>
     <!-- Packages from dotnet/corefx -->
     <MicrosoftBclAsyncInterfacesPackageVersion>1.1.0-preview3.19530.2</MicrosoftBclAsyncInterfacesPackageVersion>
     <MicrosoftCSharpPackageVersion>4.7.0-preview3.19530.2</MicrosoftCSharpPackageVersion>