change "anonymous" back to func.AuthLevel.ANONYMOUS constant

Author: ankardon

articles/azure-functions/functions-add-output-binding-azure-sql-vs-code.md

@@ -228,7 +228,7 @@ import uuid
 app = func.FunctionApp()
 
 @app.function_name(name="HttpTrigger1")
-@app.route(route="hello", auth_level="anonymous")
+@app.route(route="hello", auth_level=func.AuthLevel.ANONYMOUS)
 @app.generic_output_binding(arg_name="toDoItems", type="sql", CommandText="dbo.ToDo", ConnectionStringSetting="SqlConnectionString",data_type=DataType.STRING)
 def test_function(req: func.HttpRequest, toDoItems: func.Out[func.SqlRow]) -> func.HttpResponse:
      logging.info('Python HTTP trigger function processed a request.')