Support for google embedding models such as text-embedding-004

[Haripritamreddy]

Google's embedding models like text-embedding-004 are mentioned as supported in the docs but we have no option to set them yet.
We can do EMBEDDINGS_PROVIDER=google and EMBEDDINGS_MODEL=text-embedding-004 as its free. We can still use it by using litellm and spinning open ai api compatable server but this is more straightforward.