fix: update prompt

# What does this PR do?


## Test Plan

llama_stack/models/llama/llama3/prompt_templates/system_prompts.py

@@ -244,6 +244,7 @@ class PythonListCustomToolGenerator(PromptTemplateGeneratorBase):  # noqa: N801
         template_str = textwrap.dedent(
             """
             If you decide to invoke any of the function(s), you MUST put it in the format of [func_name1(params_name1=params_value1, params_name2=params_value2...), func_name2(params)]
+            For a boolean parameter, be sure to use `True` or `False` (capitalized) for the value.
             You SHOULD NOT include any other text in the response.
 
             Here is a list of functions in JSON format that you can invoke.