The sentence transformers was a dup of the HF one.
This is a breaking change (model_name vs. model) for anyone using
`SentenceTransformerEmbeddings(model="some/nondefault/model")`, but
since it was landed only this week it seems better to do this now rather
than doing a wrapper.
## Why this PR?
Fixes#2624
There's a missing import statement in AzureOpenAI embeddings example.
## What's new in this PR?
- Import `OpenAIEmbeddings` before creating it's object.
## How it's tested?
- By running notebook and creating embedding object.
Signed-off-by: letmerecall <girishsharma001@gmail.com>
