[browser][WBT] Remove MT signalR tests

[ilonatommy]

Fixes #106807, fixes #107931.

They can be added once MT is fully operational.

[Copilot]

Pull Request Overview

This PR removes an ActiveIssue attribute that was blocking SignalR client tests in the WebAssembly Build Tests (WBT), allowing these tests to run again after they were previously disabled due to issue #106807.

• Removes the [ActiveIssue] attribute that was preventing SignalR WBT tests from running
• Re-enables SignalR client tests for both Debug and Release configurations with LongPolling transport

Comments suppressed due to low confidence (1)

[ilonatommy]

This requires some updates after refactoring.

    Wasm.Build.Tests.AspNetCore.SignalRClientTests.SignalRPassMessageWasmBrowser(config: Debug, transport: "LongPolling") [STARTING]
    Wasm.Build.Tests.AspNetCore.SignalRClientTests.SignalRPassMessageWasmBrowser(config: Debug, transport: "LongPolling") [FAIL]
      System.Exception : /root/helix/work/workitem/e/wbt artifacts/SignalRClientTests_Debug_False_hgzgqfdd_rnz_鿀蜒枛遫䡫煉/AspNetCoreServer/WasmBasicTestApp.csproj does not exist
      Stack Trace:
        /_/src/mono/wasm/Wasm.Build.Tests/BuildTestBase.cs(273,0): at Wasm.Build.Tests.BuildTestBase.AddItemsPropertiesToProject(String projectFile, String extraProperties, String extraItems, String insertAtEnd)
        /_/src/mono/wasm/Wasm.Build.Tests/Templates/WasmTemplateTestsBase.cs(128,0): at Wasm.Build.Tests.WasmTemplateTestsBase.UpdateProjectFile(String projectFilePath, Boolean runAnalyzers, String extraProperties, String extraItems, String insertAtEnd)
        /_/src/mono/wasm/Wasm.Build.Tests/Templates/WasmTemplateTestsBase.cs(119,0): at Wasm.Build.Tests.WasmTemplateTestsBase.CopyTestAsset(Configuration config, Boolean aot, TestAsset asset, String idPrefix, Nullable`1 appendUnicodeToPath, Boolean runAnalyzers, String extraProperties, String extraItems, String insertAtEnd)
        /_/src/mono/wasm/Wasm.Build.Tests/SignalRTestsBase.cs(26,0): at Wasm.Build.Tests.SignalRTestsBase.SignalRPassMessage(String staticWebAssetBasePath, Configuration config, String transport)
        /_/src/mono/wasm/Wasm.Build.Tests/AspNetCore/SignalRClientTests.cs(26,0): at Wasm.Build.Tests.AspNetCore.SignalRClientTests.SignalRPassMessageWasmBrowser(Configuration config, String transport)
        --- End of stack trace from previous location ---
``