Fix failure to render ChildPages when ApiPath has more than one segment (e.g. test/api)

Author: ociaw

input/_Layout.cshtml

@@ -73,7 +73,7 @@
             }
             @await Html.PartialAsync("_Splash")
             @{
-                string section = Document.Destination.Segments.Length > 1 ? Document.Destination.Segments[0].ToString() : null;
+                string section = Document.Destination.Segments.Length > 1 ? @Context.GetString(DocsKeys.ApiPath) : null;
                 IDocument root = OutputPages.Get(section + "/index.html");
             }
             <div class="flex-grow-1 d-flex flex-column">
@@ -166,6 +166,10 @@
                                         {
                                             IgnoreSection(SectionNames.Sidebar);
                                         }
+                                        if (IsSectionDefined(SectionNames.ChildPages))
+                                        {
+                                            IgnoreSection(SectionNames.ChildPages);
+                                        }
 
                                         <div id="content" class="offset-lg-2 col-12 col-lg-8 p-4 pt-md-0 bg-white">
 @* Render the body without indenting in case it contains things like directives *@