Updates whatsnew file for v13.1

Author: ramaroesilva

docs/sphinx/source/whatsnew/v0.13.1.rst

@@ -19,8 +19,11 @@ Bug fixes
 
 Enhancements
 ~~~~~~~~~~~~
-
-
+* Rename parameter name ``aparent_azimuth`` to ``solar_azimuth`` in :py:func:`~pvlib.tracking.singleaxis`.
+  (:issue:`2479`, :pull:`2480`)
+* Adds k coefficient in :py:func:`~pvlib.temperature.ross`
+  (:issue:`2506`, :pull:`2521`)
+  
 Documentation
 ~~~~~~~~~~~~~
 * Substantiate definitions of solar/surface azimuth/zenith and aoi on the
@@ -48,4 +51,5 @@ Contributors
 ~~~~~~~~~~~~
 * Elijah Passmore (:ghuser:`eljpsm`)
 * Rajiv Daxini (:ghuser:`RDaxini`)
-* Omar Bahamida (:ghuser:`OmarBahamida`)
+* Omar Bahamida (:ghuser:`OmarBahamida`)
+* Rodrigo Amaro e Silva (:ghuser:`ramaroesilva`)