similarity_search_with_score() raises NotImplementedError

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#### Environment details

- OS type and version: MacOS
- Python version: python 3.12
- pip version: 24.0
- `langchain-google-firestore` version: langchain-google-firestore 0.3.0

#### Steps to reproduce

1. Install langchain-google-firestore 0.3.0 and run the code below

#### Code example

```python
from langchain_core.documents import Document
from langchain_google_firestore import FirestoreVectorStore
from langchain_google_vertexai import VertexAIEmbeddings

embeddings = VertexAIEmbeddings(model_name="textembedding-gecko@latest")

# Load data
data = ["blue and yellow makes green", "red and orange makes yellow", "white and black makes grey"]

docs = [Document(page_content=d) for d in data]
vector_store = FirestoreVectorStore.from_documents(
collection="colors",
documents=docs,
embedding=embeddings,
)

vector_store.similarity_search_with_score("green") # this raises NotImplementError
```

#### Stack trace
```
Traceback (most recent call last):
File "/demo/vector_store_demo/main.py", line 21, in
vector_store.similarity_search_with_score("green")
File "/demo/.venv/lib/python3.12/site-packages/langchain_core/vectorstores/base.py", line 679, in similarity_search_with_score
raise NotImplementedError
NotImplementedError
```