Apply suggestion from @lucaspimentel

Co-authored-by: Lucas Pimentel <[email protected]>

Author: pablomartinezbernardo

tracer/test/test-applications/integrations/Samples.CosmosDb.Vnext/App.config

@@ -4,6 +4,10 @@
         <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.1" />
     </startup>
   <appSettings>
+    <!--
+        This is the well-known Cosmos DB emulator key, safe for public repositories.
+        See https://learn.microsoft.com/en-us/azure/cosmos-db/emulator
+    -->
     <add key="PrimaryKey" value="C2y6yDjf5/R+ob0N8A7Cgv30VRDJIWEHLM+4QDU5DE2nQ9nDuVTqobD4b8mGGyPMbIZnqyMsEcaGQy67XIw/Jw==" />
   </appSettings>
 </configuration>