refs and cleanup

Author: SimonCropp

src/Directory.Packages.props

@@ -18,7 +18,7 @@
     <PackageVersion Include="Microsoft.SqlServer.TransactSql.ScriptDom" Version="170.128.0" />
     <PackageVersion Include="NUnit" Version="4.4.0" />
     <PackageVersion Include="NUnit3TestAdapter" Version="5.2.0" />
-    <PackageVersion Include="Polyfill" Version="9.0.3" />
+    <PackageVersion Include="Polyfill" Version="9.1.0" />
     <PackageVersion Include="ProjectDefaults" Version="1.0.162" />
     <PackageVersion Include="System.Data.SqlClient" Version="4.9.0" />
     <PackageVersion Include="Verify" Version="31.7.1" />