(Chroma): Small Fix in add_texts when checking for embeddings (#29766)

- **Description:** Small fix in `add_texts` to make embedding
nullability is checked properly.
- **Issue:** #29765

---------

Co-authored-by: Chester Curme <chester.curme@gmail.com>

libs/partners/chroma/langchain_chroma/vectorstores.py

@@ -547,7 +547,9 @@ def add_texts(
                 metadatas = [metadatas[idx] for idx in non_empty_ids]
                 texts_with_metadatas = [texts[idx] for idx in non_empty_ids]
                 embeddings_with_metadatas = (
-                    [embeddings[idx] for idx in non_empty_ids] if embeddings else None
+                    [embeddings[idx] for idx in non_empty_ids]
+                    if embeddings is not None
+                    else None
                 )
                 ids_with_metadata = [ids[idx] for idx in non_empty_ids]
                 try: