Update release notes

Signed-off-by: Simon Völcker <simon.voelcker@frequenz.com>

Author: simonvoelcker

RELEASE_NOTES.md

@@ -15,3 +15,7 @@ This release makes incremental improvements to the client and the quantity types
 - All methods on `Quantity` types are now `const`.
 
 - `Quantity` types have two new methods `min` and `max`, similar to the `min` and `max` methods on fundamental numerical types.
+
+- New method `MockMicrogridApiClient::augment_electrical_component_bounds` captures requests so that these can be used in test cases. Obtain the list of captured requests using `MockMicrogridApiClient::augment_bounds_calls_handle` (also new).
+
+- New method `MockComponent.add_component_bounds` allows to add metric bounds to a mock component.