fix: Update docstring format for DeepJSCC model implementation

Author: selimfirat

kaira/models/image/bourtsoulatze2019_deepjscc.py

@@ -1,7 +1,4 @@
-"""Implementation of the DeepJSCC model from Bourtsoulatze et al.
-
-(2019).
-"""
+"""Implementation of the DeepJSCC model from :cite:`bourtsoulatze2019deep`."""
 
 from typing import Any, Optional