Update feature matrix for Astra DB vector store integration (#1159)

## Overview

This PR updates the feature matrix for the Astra DB vector store
integration.

## Type of change

**Type:** Update existing documentation

## Checklist
- [x] I have read the [contributing guidelines](README.md)
- [?] I have tested my changes locally using `docs dev`
- [n/a] All code examples have been tested and work correctly
- [n/a] I have used **root relative** paths for internal links
- [n/a] I have updated navigation in `src/docs.json` if needed
- I have gotten approval from the relevant reviewers

## Additional notes

This PR marks these two attributes as "yes" for the Astra DB Vector
Store component: **passes standard tests** and **multi tenancy**.

For the first item, the component [uses the entire vectorstore
suite](https://github.com/langchain-ai/langchain-datastax/blob/main/libs/astradb/tests/integration_tests/standard_tests/test_vectorstore.py)
from the `langchain-tests` in its CI/CD and passes it.

For the multi-tenancy, Astra DB is a cloud database: as such, is it my
understanding that it is inherently multitenant, as each user comes with
their own auth token and accesses their own databases there through
DB-specific endpoints ([see e.g.
here](https://github.com/langchain-ai/langchain-datastax/blob/main/libs/astradb/langchain_astradb/vectorstores.py#L770-L776)).
In that respect, it is not different than e.g. the Mongo DB Atlas vector
store, likewise marked as multitenant in the feature matrix.

Co-authored-by: Mason Daugherty <mason@langchain.dev>

Author: sl-at-ibm

src/oss/python/integrations/vectorstores/index.mdx

@@ -384,7 +384,7 @@ from langchain_core.vectorstores import InMemoryVectorStore
 vector_store = InMemoryVectorStore(embeddings)
 ```
 </Accordion>
-<Accordion title="AstraDB">
+<Accordion title="Astra DB">
 
 <CodeGroup>
 ```bash pip
@@ -645,7 +645,7 @@ vector_store = QdrantVectorStore(
 
 | Vectorstore | Delete by ID | Filtering | Search by Vector | Search with score | Async | Passes Standard Tests | Multi Tenancy | IDs in add Documents |
 |------------|-------------|-----------|-----------------|------------------|--------|---------------------|---------------|-------------------|
-| [`AstraDBVectorStore`](/oss/integrations/vectorstores/astradb) | ✅ | ✅ | ✅ | ✅ | ✅ | ❌ | ❌ | ✅ |
+| [`AstraDBVectorStore`](/oss/integrations/vectorstores/astradb) | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ |
 | [`AzureCosmosDBNoSqlVectorStore`](/oss/integrations/vectorstores/azure_cosmos_db_no_sql) | ✅ | ✅ | ✅ | ✅ | ❌ | ✅ | ✅ | ✅ |
 | [`AzureCosmosDBMongoVCoreVectorStore`](/oss/integrations/vectorstores/azure_cosmos_db_mongo_vcore) | ✅ | ✅ | ✅ | ✅ | ❌ | ✅ | ✅ | ✅ |
 | [`Chroma`](/oss/integrations/vectorstores/chroma) | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ |