Fix url for parameter sample (#10679)

* Fixing url from microsoft aspire to aspire gh

* rename parametere2e program.cs to apphost.cs

Author: maddymontaquila

playground/ParameterEndToEnd/ParameterEndToEnd.AppHost/Program.cs renamed to playground/ParameterEndToEnd/ParameterEndToEnd.AppHost/AppHost.cs

@@ -36,7 +36,7 @@ And has another paragraph.
 
         And a list:
         - Item 1
-        - Item 2 (and a [hyperlink](https://aka.ms/aspire))
+        - Item 2 (and a [hyperlink](https://github.com/dotnet/aspire))
         - Item 3
         """, enableMarkdown: true);