Remove text-davinci-003 everywhere

[zsimjee]

https://github.com/guardrails-ai/guardrails/blob/8833c0507d58825b2712d7660b14efff7dc69855/guardrails/llm_providers.py#L99

It's used everywhere. It's our default model for openai completions. For each appearance we need to find which new model works as well as 003 did, and update the model to that.