It seems we need dotnet 10 now

Author: johnsimons

.devcontainer/Dockerfile

@@ -1,6 +1,5 @@
-# NET 6.0 is required for the docstool
 # For more options see https://github.com/devcontainers/images/tree/main/src/dotnet
-FROM mcr.microsoft.com/devcontainers/dotnet:9.0
+FROM mcr.microsoft.com/devcontainers/dotnet:10.0-preview
 
 # Required dependency for docstool libskiasharp
 RUN sudo apt-get update && sudo apt-get install fontconfig -y