[wasi] Disable build in .NET 10

[Copilot]

Disables WASI builds and workload usage for .NET 10, similar to the changes made in PR #108877 for .NET 9.

The 'wasi-experimental' workload is not supported in .NET 10. This change makes it explicit, so that users are not misled into thinking that the workload is supported. The WASI experiment continues to be developed but is disabled for this release.

Changes made:

1. Pipeline changes (eng/pipelines/runtime.yml):

   • Commented out WASI build targets in MonoAOTOffsets platform matrix
   • Commented out WASI simple-wasm-build-tests template

2. Test job removal (eng/testing/scenarios/BuildWasiAppsJobsList.txt):

   • Cleared all WASI test jobs from the build job list

3. Workload error target (WorkloadManifest.Wasi.targets.in):

   • Added build failure target that triggers when RuntimeIdentifier is wasi-wasm
   • Displays clear error message: "The 'wasi-experimental' workload is not supported in .NET 10."

Verification:

• Normal library builds continue to work correctly
• WASI-specific CI/CD pipelines are disabled
• Users attempting to use WASI workload will receive a clear error message

Fixes #117931.

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[Copilot]

Pull Request Overview

This PR disables WASI (WebAssembly System Interface) build support and workload usage for .NET 10, aligning with previous changes made for .NET 9. The changes ensure users receive clear error messages when attempting to use unsupported WASI functionality.

Key changes:

• Disables WASI build pipelines in CI/CD configuration
• Removes all WASI-related test jobs from execution
• Adds explicit build failure with informative error message for WASI workload usage

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
WorkloadManifest.Wasi.targets.in	Adds build target that fails with clear error message when WASI runtime identifier is used
BuildWasiAppsJobsList.txt	Removes all WASI test jobs, leaving file with only empty line
eng/pipelines/runtime.yml	Comments out WASI build template configuration in pipeline

Comments suppressed due to low confidence (1)

[pavelsavara]

/azp run runtime-wasm

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[akoeplinger]

LGTM but merging it now will mean that people who have been using it won't have a way to experiment until we have net11 builds which will take a while. Should we add an env var opt out ?

[maraf]

LGTM but merging it now will mean that people who have been using it won't have a way to experiment until we have net11 builds which will take a while. Should we add an env var opt out ?

I guess it's fine to stick to previous preview before there is a .NET 11 preview