Move test projects from src/ to tests/ (#11357)

* Update gitignore

* Move csproj

* Update project references

* Update solutions

* Update build scripts

* Tests used to share editorconfig with projects in src

* Fix broken tests.

* Stop copying around .editorconfig

merged root one with linting

* csharp_style_expression_bodied -> suggestion

* Move StyleCop rulesets to matching directories and update shared build properties

* Remove legacy build files, update NuGet.cofig and solution files

* Restore myget source

* Clean up .gitignore

* Update .gitignore

* Move new test classes to tests after merge

* Gitignore + nuget config

* Move new test

Co-authored-by: Ronald Barendse <ronald@barend.se>

tests/Umbraco.Tests.Integration/Implementations/TestLifetime.cs

@@ -0,0 +1,19 @@
+// Copyright (c) Umbraco.
+// See LICENSE for more details.
+
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Hosting;
+
+namespace Umbraco.Cms.Tests.Integration.Implementations
+{
+    /// <summary>
+    /// Ensures the host lifetime ends as soon as code execution is done
+    /// </summary>
+    public class TestLifetime : IHostLifetime
+    {
+        public Task StopAsync(CancellationToken cancellationToken) => Task.CompletedTask;
+
+        public Task WaitForStartAsync(CancellationToken cancellationToken) => Task.CompletedTask;
+    }
+}