Updates "What's New" docs for change

Author: jerluc

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

@@ -29,6 +29,8 @@ Enhancements
   (:pull:`2500`)
 * :py:func:`pvlib.spectrum.spectral_factor_firstsolar` no longer emits warnings
   when airmass and precipitable water values fall out of range. (:pull:`2512`)
+* Allows reading TMY data from a Path or file-like object in :py:func:`~pvlib.iotools.read_tmy3`.
+  (:pull:`2544`, :ghuser:`jerluc`)
 
 Documentation
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