Fixed test case for chroma db (#358)

tests/vectordb/test_chroma_db.py

@@ -17,7 +17,7 @@ class TestChromaDbHosts(unittest.TestCase):
         host = "test-host"
         port = "1234"
 
-        with patch.object(chromadb, "Client") as mock_client:
+        with patch.object(chromadb, "HttpClient") as mock_client:
             _db = ChromaDB(host=host, port=port, embedding_fn=len)
 
         expected_settings = Settings(