Add a GriptapeCloudEmbeddingDriver

[shhlife]

Griptape 1.4 offers a GriptapeCloudPromptDriver which is handy, but quite often people will want to be able to use RAG, use tools off_prompt, etc - and in order to do that they need an Embedding Driver. We should include one as part of Griptape Cloud.

This also brings up other drivers we may want to host.. like AudioTranscription, ImageGeneration, etc.

Ideally we have a GriptapeCloudDriversConfig and use that as the default instead of OpenAI

[collindutter]

@shhlife this is a great idea but Griptape Cloud does not yet provide such functionality. Let's get a discussion going over there.

Let's keep this discussion around for when it's time for the framework work.