Update CHANGELOG

CHANGELOG.md

@@ -7,7 +7,6 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Utilities to operate on Gymnasium spaces (`Box`, `Discrete`, `MultiDiscrete`, `Tuple` and `Dict`)
 - `parse_device` static method in ML framework configuration (used in library components to set up the device)
 - Model instantiator support for different shared model structures in PyTorch
-- Support for other model types than Gaussian and Deterministic in runners
 - Support for automatic mixed precision training in PyTorch
 - `init_state_dict` method to initialize model's lazy modules in PyTorch
 - Model instantiators `fixed_log_std` parameter to define immutable log standard deviations
@@ -20,6 +19,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Drop support for PyTorch versions prior to 1.10 (the previous supported version was 1.9)
 - Update KL Adaptive learning rate scheduler implementation to match Optax's behavior in JAX
 - Update AMP agent to use the environment's terminated and truncated data, and the KL Adaptive learning rate scheduler
+- Update runner implementations to support definition of arbitrary agents and their models
 - Speed up PyTorch implementation:
   - Disable argument checking when instantiating distributions
   - Replace PyTorch's `BatchSampler` by Python slice when sampling data from memory