docs: fix prompt message (#1930)

## Description

> Should include a concise description of the changes (bug or feature),
it's
> impact, along with a summary of the solution

## PR Checklist

> Thank you for opening a Pull Request! Before submitting your PR, there
are a
> few things you can do to make sure it goes smoothly:

- [x] Make sure you reviewed

[CONTRIBUTING.md](https://github.com/googleapis/genai-toolbox/blob/main/CONTRIBUTING.md)
- [ ] Make sure to open an issue as a

[bug/issue](https://github.com/googleapis/genai-toolbox/issues/new/choose)
  before writing your code! That way we can discuss the change, evaluate
  designs, and agree on the general idea
- [x] Ensure the tests and linter pass
- [ ] Code coverage does not decrease (if any source code was changed)
- [ ] Appropriate docs were updated (if necessary)
- [ ] Make sure to add `!` if this involve a breaking change

🛠️ Fixes #<issue_number_goes_here>

docs/en/resources/prompts/_index.md

@@ -62,7 +62,7 @@ Prompts defined in your `tools.yaml` can be seamlessly integrated with the Gemin
     Eg.
 
     ```bash
-    Please review this Python code:\ndef hello():\n    print('world')
+    Please review the following code for quality, correctness, and potential improvements: \ndef hello():\n    print('world')
     ```
 
 5. **Response:** This completed prompt is then sent to the Gemini model, and the model's response is displayed back to you in the CLI.