Add IAsyncComponent to allow async initialize/terminate (#16536)

* Add IAsyncComponent

* Rewrite to use IAsyncComposer

* Add AsyncComponentBase and RuntimeAsyncComponentBase

* Remove manual disposing of components on restart

src/Umbraco.Core/Extensions/ObjectExtensions.cs

@@ -41,8 +41,9 @@ public static class ObjectExtensions
     public static IEnumerable<T> AsEnumerableOfOne<T>(this T input) => Enumerable.Repeat(input, 1);
 
     /// <summary>
+    /// Disposes the object if it implements <see cref="IDisposable" />.
     /// </summary>
-    /// <param name="input"></param>
+    /// <param name="input">The object.</param>
     public static void DisposeIfDisposable(this object input)
     {
         if (input is IDisposable disposable)