community: Add support for specifying hybrid search for Databricks vector search (#23528)

**Description:**

Databricks Vector Search recently added support for hybrid
keyword-similarity search.
See [usage
examples](https://docs.databricks.com/en/generative-ai/create-query-vector-search.html#query-a-vector-search-endpoint)
from their documentation.

This PR updates the Langchain vectorstore interface for Databricks to
enable the user to pass the *query_type* parameter to
*similarity_search* to make use of this functionality.
By default, there will not be any changes for existing users of this
interface. To use the new hybrid search feature, it is now possible to
do

```python
# ...
dvs = DatabricksVectorSearch(index)
dvs.similarity_search("my search query", query_type="HYBRID")
```

Or using the retriever:

```python
retriever = dvs.as_retriever(
    search_kwargs={
        "query_type": "HYBRID",
    }
)
retriever.invoke("my search query")
```

---------

Co-authored-by: Bagatur <22008038+baskaryan@users.noreply.github.com>
Co-authored-by: Erick Friis <erick@langchain.dev>

docs/docs/integrations/vectorstores/databricks_vector_search.ipynb

@@ -174,7 +174,10 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "## Similarity search"
+    "## Similarity search\n",
+    "Optional keyword arguments to similarity_search include specifying k number of documents to retrive, \n",
+    "a filters dictionary for metadata filtering based on [this syntax](https://docs.databricks.com/en/generative-ai/create-query-vector-search.html#use-filters-on-queries),\n",
+    "as well as the [query_type](https://api-docs.databricks.com/python/vector-search/databricks.vector_search.html#databricks.vector_search.index.VectorSearchIndex.similarity_search) which can be ANN or HYBRID "
    ]
   },
   {