Use xunit.runner.json in Helix runs (#19922)

eng/helix/content/default.runner.json

@@ -0,0 +1,5 @@
+{
+  "longRunningTestSeconds": 60,
+  "diagnosticMessages": true,
+  "maxParallelThreads": -1
+}

eng/helix/content/runtests.cmd

@@ -49,6 +49,11 @@ echo Creating nuget restore directory: %NUGET_RESTORE%
 mkdir %NUGET_RESTORE%
 mkdir logs
 
+REM "Rename default.runner.json to xunit.runner.json if there is not a custom one from the project"
+if not EXIST ".\xunit.runner.json" (
+    copy default.runner.json xunit.runner.json
+)
+
 dir
 
 %DOTNET_ROOT%\dotnet vstest %$target% -lt >discovered.txt

eng/helix/content/runtests.sh

@@ -108,7 +108,12 @@ then
 
     # Ensure tools are on on PATH
     export PATH="$PATH:$DOTNET_CLI_HOME/.dotnet/tools"
+fi
 
+# Rename default.runner.json to xunit.runner.json if there is not a custom one from the project
+if [ ! -f "xunit.runner.json" ]
+then
+    cp default.runner.json xunit.runner.json
 fi
 
 if [ -e /proc/self/coredump_filter ]; then

src/ProjectTemplates/Directory.Build.props

@@ -8,4 +8,10 @@
   </PropertyGroup>
 
   <Import Project="TemplateProjects.props" Condition="'$(IsTestProject)' != 'true' AND '$(IsTestAssetProject)' != 'true'" />
+
+  <ItemGroup Condition="'$(IsTestProject)' == 'true'">
+    <Content Include="$(MSBuildThisFileDirectory)xunit.runner.json" Link="xunit.runner.json">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
+  </ItemGroup>
 </Project>

src/ProjectTemplates/xunit.runner.json

@@ -0,0 +1,5 @@
+{
+  "longRunningTestSeconds": 60,
+  "diagnosticMessages": true,
+  "maxParallelThreads": -1
+}