doc: changelog: Updated changelog to specify shutdown sample changes

Updated changelog to document updated wi-fi shutdown sample and
addition of one-shot and continuous modes of operation.

Signed-off-by: Bansidhar Mangalwedhekar <[email protected]>

Author: bama-nordic

doc/nrf/releases_and_maturity/releases/release-notes-changelog.rst

@@ -569,6 +569,10 @@ Wi-Fi samples
 
   * Updated :ref:`wifi_radio_test` and :ref:`wifi_radio_test_sd` samples to clarify platform support for single-domain and multi-domain radio tests.
 
+* :ref:`wifi_shutdown_sample`:
+
+  * Updated the sample to include both One-shot and Continuous modes of operations.
+
 Other samples
 -------------