Upgrade pulumi/pulumi-dotnet LANGUAGE_VERSION from out-of-support 8.0 to 10.0 (latest LTS)

[mhstins-bliksund]

The main readme.md claims "The pulumi/pulumi-dotnet image is based on the default .NET version, which is currently 8.0".
The latest supported LTS dotnet release is currently 10.0.
The highest .NET version Pulumi container is currently still pulumi/pulumi-dotnet-9.0

I'd like to see support for the latest .NET LTS in the "default" container and see a new pulumi/pulumi-dotnet-10.0

[tgummerer]

Hi @mhstins-bliksund. I've opened #743 to add the pulumi/pulumi-dotnet-10.0 container. Updating the default version in the pulumi/pulumi container is probably something we'll only do after .NET 8.0 is EOL, as that's a breaking change for users, so we want to avoid updates there when we can.

[jkodroff]

EOL (at the time of writing - MSFT has changed the EOL dates in the past) for .NET 8 and 9 are November 10, 2026.

Source: https://dotnet.microsoft.com/en-us/platform/support/policy/dotnet-core