chore(deps): update dependency memorypack to v1.20.3

Author: renovate[bot]

SerializationBenchmarks.csproj

@@ -22,7 +22,7 @@
         <PackageReference Include="GroBuf" Version="1.9.2" />
         <PackageReference Include="Hyperion" Version="0.12.2" />
         <PackageReference Include="Jil" Version="2.17.0" />
-        <PackageReference Include="MemoryPack" Version="1.20.2" />
+        <PackageReference Include="MemoryPack" Version="1.20.3" />
         <PackageReference Include="MessagePack" Version="2.5.140" />
         <PackageReference Include="MongoDB.Bson" Version="2.24.0" />
         <PackageReference Include="MsgPack.Cli" Version="1.0.1" />