Use contraint-based assert and switch back to .NET 8 for testing

.editorconfig

@@ -84,6 +84,7 @@ dotnet_diagnostic.CA1845.severity = none        # CA1845: Use span-based 'string
 dotnet_diagnostic.CA1846.severity = none        # CA1846: Prefer 'AsSpan' over 'Substring'
 dotnet_diagnostic.CA1847.severity = none        # CA1847: Use char literal for a single character lookup
 dotnet_diagnostic.CA1852.severity = suggestion  # CA1852: Seal internal types
+dotnet_diagnostic.CA1854.severity = suggestion  # CA1854: Prefer the 'IDictionary.TryGetValue(TKey, out TValue)' method
 dotnet_diagnostic.CA1859.severity = suggestion  # CA1859: Use concrete types when possible for improved performance
 dotnet_diagnostic.CA1861.severity = suggestion  # CA1861: Avoid constant arrays as arguments
 dotnet_diagnostic.CA1863.severity = none        # CA1863: Use 'CompositeFormat'

.github/workflows/main.yml

@@ -35,11 +35,6 @@ jobs:
       uses: actions/setup-dotnet@v1
       with:
         dotnet-version: '8.0.x'
-    - name: Setup .NET 9.0
-      uses: actions/setup-dotnet@v1
-      with:
-        dotnet-version: '9.0.x'
-        include-prerelease: true
     - name: Version Information
       run: |
         dotnet --info

Build/steps.yml

@@ -43,17 +43,10 @@ steps:
       version: '7.0.x'
 
   - task: UseDotNet@2
-    displayName: Install .NET 8.0 runtime for testing
-    inputs:
-      packageType: 'runtime'
-      version: '8.0.x'
-
-  - task: UseDotNet@2
-    displayName: Install .NET 9.0 SDK for build
+    displayName: Install .NET 8.0 SDK for build
     inputs:
       packageType: 'sdk'
-      version: '9.0.x'
-      includePreviewVersions: true
+      version: '8.0.x'
 
   # Set Mono version on macOS
   - ${{ if eq(parameters.os, 'macOS') }}:

Src/IronPythonTest/Stress/Engine.cs

@@ -48,7 +48,7 @@ public void ScenarioXGC() {
                 ScriptScope scope = _pe.CreateScope();
                 scope.SetVariable("x", "Hello");
                 _pe.CreateScriptSourceFromFile(System.IO.Path.Combine(Common.InputTestDirectory, "simpleCommand.py")).Execute(scope);
-                Assert.AreEqual(_pe.CreateScriptSourceFromString("x").Execute<int>(scope), 1);
+                Assert.That(1, Is.EqualTo(_pe.CreateScriptSourceFromString("x").Execute<int>(scope)));
                 scope = null;
             }