Adjust default openai model id for baibot (`gpt-4o` -> gpt-4o-2024-08-06)

`gpt-4o` will point to `gpt-4o-2024-08-06` after 2nd of October 2024
anyway. At that time, we can revert to pointing to `gpt-4o`.

The reason `gpt-4o-2024-08-06` was chosen now instead of `gpt-4o`:

- the `max_response_tokens` configuration was set to 16k, which matches
  `gpt-4o-2024-08-06`, but is too large for `gpt-4o` (max 4k)

- baibot's own configs for dynamically created agents, as well as static
  config examples use `gpt-4o-2024-08-06` and the larger
  `max_response_tokens` value

docs/configuring-playbook-bot-baibot.md

@@ -249,7 +249,7 @@ matrix_bot_baibot_config_agents_static_definitions_openai_config_api_key: "YOUR_
 # matrix_bot_baibot_config_agents_static_definitions_openai_config_text_generation_prompt: "{{ matrix_bot_baibot_config_agents_static_definitions_prompt }}"
 
 # If you'd like to use another text-generation agent, uncomment and adjust:
-# matrix_bot_baibot_config_agents_static_definitions_openai_config_text_generation_model_id: gpt-4o
+# matrix_bot_baibot_config_agents_static_definitions_openai_config_text_generation_model_id: gpt-4o-2024-08-06
 
 # See `defaults/main.yml` in the baibot role for more configuration options.
 ```

roles/custom/matrix-bot-baibot/defaults/main.yml

@@ -356,7 +356,7 @@ matrix_bot_baibot_config_agents_static_definitions_openai_config_api_key: ""
 
 matrix_bot_baibot_config_agents_static_definitions_openai_config_text_generation_enabled: true
 # For valid model choices, see: https://platform.openai.com/docs/models
-matrix_bot_baibot_config_agents_static_definitions_openai_config_text_generation_model_id: gpt-4o
+matrix_bot_baibot_config_agents_static_definitions_openai_config_text_generation_model_id: gpt-4o-2024-08-06
 # The prompt text to use (can be null or empty to not use a prompt).
 # See: https://huggingface.co/docs/transformers/en/tasks/prompting
 matrix_bot_baibot_config_agents_static_definitions_openai_config_text_generation_prompt: "{{ matrix_bot_baibot_config_agents_static_definitions_prompt }}"