Upgrade Orleans 2.1.2

Author: lfzm

src/Ocelot.OrleansHttpGateway/Ocelot.OrleansHttpGateway.csproj

@@ -22,7 +22,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Orleans.Core" Version="2.0.3" />
+    <PackageReference Include="Microsoft.Orleans.Core" Version="2.1.2" />
     <PackageReference Include="Ocelot" Version="12.0.1" />
   </ItemGroup>