removed duplicate step

Author: JoshuaPartlow

docs/ide/quickstart-python.md

@@ -173,8 +173,6 @@ You're now ready to add a bit of Python code to implement a minimal web app.
     ![Setting the startup file for a project in Solution Explorer](media/quickstart-python-05-set-as-startup-file-2019.png)
     ::: moniker-end
 
-1. Right-click *app.py* in **Solution Explorer** and select **Set as startup file**. This command identifies the code file to launch in Python when running the app.
-
 2. Right-click the project in **Solution Explorer** and select **Properties**. Then select the **Debug** tab and set the **Port Number** property to `4449`. This step ensures that Visual Studio launches a browser with `localhost:4449` to match the `app.run` arguments in the code.
 
 3. Select **Debug > Start Without Debugging** (**Ctrl**+**F5**), which saves changes to files and runs the app.