Fix validate_json file error when cwd != project root

[mickjagger19]

Background

If running from any directory other than Auto-GPT, the program will crash, giving the following error message:

 File "AppData\Local\Programs\Python\Python311\Lib\site-packages\click\decorators.py", line 26, in new_func
    return f(get_current_context(), *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "Auto-GPT\autogpt\cli.py", line 151, in main
    agent.start_interaction_loop()
  File "Auto-GPT\autogpt\agent\agent.py", line 86, in start_interaction_loop
    validate_json(assistant_reply_json, "llm_response_format_1")
  File "Auto-GPT\autogpt\json_utils\utilities.py", line 38, in validate_json
    with open(f"autogpt/json_utils/{schema_name}.json", "r") as f:
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
FileNotFoundError: [Errno 2] No such file or directory: 'autogpt/json_utils/llm_response_format_1.json'

This is caused by wrong location of llm_response_format_1.json, which can be easily fixed by building the path from concatenating script path and the json file name.

Changes

Change the building process of the path of llm_response_format_1.json into:

    script_dir = os.path.dirname(__file__)

    with open(os.path.join(script_dir, f"{schema_name}.json"), "r") as f:
        ...

Documentation

Test Plan

PR Quality Checklist

• My pull request is atomic and focuses on a single change.
• I have thoroughly tested my changes with multiple different prompts.
• I have considered potential risks and mitigations for my changes.
• I have documented my changes clearly and comprehensively.
• I have not snuck in any "extra" small tweaks changes

[Pwuts]

So this merged into stable... I should have caught that and didn't, but just to be clear: PRs should be merged into master, NOT stable.