Update initial usage example (#16824)

* Update initial usage example

After running the initial usage example, it wasn't clear how to know whether the command ran successfully. This adds an instruction to view the output of the running Wasm module.

* Update desktop/wasm/index.md

---------

Co-authored-by: Allie Sadler <102604716+aevesdocker@users.noreply.github.com>

desktop/wasm/index.md

@@ -47,6 +47,8 @@ $ docker run -dp 8080:8080 \
   michaelirwin244/wasm-example
 ```
 
+After running this command, you can visit [http://localhost:8080/](http://localhost:8080/) to see the "Hello world" output from this example module.
+
 > Got an error message? Head to the [troubleshooting section](#troubleshooting)
 > for help.