bump Smdn.Net.MuninNode.Hosting up to 3.1.0

Author: smdn

examples/Smdn.Net.MuninNode.Hosting/getting-started/Program.csproj

@@ -10,7 +10,6 @@ SPDX-License-Identifier: MIT
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Hosting" Version="8.0.0" />
     <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="8.0.0" />
-    <PackageReference Include="Smdn.Net.MuninNode" Version="2.3.0" />
-    <PackageReference Include="Smdn.Net.MuninNode.Hosting" Version="3.0.0" />
+    <PackageReference Include="Smdn.Net.MuninNode.Hosting" Version="3.1.0" />
   </ItemGroup>
 </Project>