Add description to the UNRELEASED.md file

docs/releases/unreleased.md

@@ -6,6 +6,14 @@ River's mini-batch methods now support pandas v2. In particular, River conforms
 
 - Added `anomaly.LocalOutlierFactor`, which is an online version of the LOF algorithm for anomaly detection that matches the scikit-learn implementation.
 
+## clustering
+
+- Add fixes to `cluster.DBSTREAM` algorithm, including:
+  - Addition of the `-` sign before the `fading_factor` in accordance with the algorithm 2 proposed by Hashler and Bolanos (2016) to allow clusters with low weights to be removed. 
+  - The new `micro_cluster` is added with the key derived from the maximum key of the existing micro clusters. If the set of micro clusters is still empty (`len = 0`), a new micro cluster is added with key 0. 
+  - `cluster_is_up_to_date` is set to `True` at the end of the `self._recluster()` function.
+
+
 ## datasets
 
 - Added `datasets.WebTraffic`, which is a dataset that counts the occurrences of events on a website. It is a multi-output regression dataset with two outputs.