Update release notes

Signed-off-by: Sahas Subramanian <[email protected]>

Author: shsms

RELEASE_NOTES.md

@@ -12,6 +12,8 @@
 
 <!-- Here goes the main new features and examples or instructions on how to use them -->
 
+- The client now supports setting reactive power for components through the new `set_reactive_power` method.
+
 ## Bug Fixes
 
 <!-- Here goes notable bug fixes that are worth a special mention or explanation -->