Update azure_cosmos_db for mongodb documentation (#23740)

added pre-filtering documentation

Thank you for contributing to LangChain!

- [x] **PR title**: "package: description"
- Where "package" is whichever of langchain, community, core,
experimental, etc. is being modified. Use "docs: ..." for purely docs
changes, "templates: ..." for template changes, "infra: ..." for CI
changes.
  - Example: "community: add foobar LLM"


- [x] **PR message**: 
    - **Description:** added filter vector search 
    - **Issue:** N/A
    - **Dependencies:** N/A
    - **Twitter handle:**: n/a


- [x] **Add tests and docs**: If you're adding a new integration, please
include - No need for tests, just a simple doc update
1. a test for the integration, preferably unit tests that do not rely on
network access,
2. an example notebook showing its use. It lives in
`docs/docs/integrations` directory.


- [x] **Lint and test**: Run `make format`, `make lint` and `make test`
from the root of the package(s) you've modified. See contribution
guidelines for more: https://python.langchain.com/docs/contributing/

Additional guidelines:
- Make sure optional dependencies are imported within a function.
- Please do not add dependencies to pyproject.toml files (even optional
ones) unless they are required for unit tests.
- Most PRs should not touch more than one package.
- Changes should be backwards compatible.
- If you are adding something to community, do not re-import it in
langchain.

If no one reviews your PR within a few days, please @-mention one of
baskaryan, efriis, eyurtsev, ccurme, vbarda, hwchase17.

docs/docs/integrations/vectorstores/azure_cosmos_db.ipynb

@@ -343,6 +343,15 @@
     "print(docs[0].page_content)"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "b63c73c7e905001c",
+   "metadata": {},
+   "source": [
+    "## Filtered vector search (Preview)\n",
+    "Azure Cosmos DB for MongoDB supports pre-filtering with $lt, $lte, $eq, $neq, $gte, $gt, $in, $nin, and $regex. To use this feature, enable \"filtering vector search\" in the \"Preview Features\" tab of your Azure Subscription. Learn more about preview features [here](https://learn.microsoft.com/azure/cosmos-db/mongodb/vcore/vector-search#filtered-vector-search-preview)."
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,