gh-150076: Fix the documented signature of warnings.deprecated (GH-153879)

(cherry picked from commit 56ad3bc)

Co-authored-by: Vyron Vasileiadis <hi@fedonman.com>
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

Author: 2 people

Doc/library/warnings.rst

@@ -551,7 +551,7 @@ Available Functions
    and calls to :func:`simplefilter`.
 
 
-.. decorator:: deprecated(msg, *, category=DeprecationWarning, stacklevel=1)
+.. decorator:: deprecated(message, /, *, category=DeprecationWarning, stacklevel=1)
 
    Decorator to indicate that a class, function or overload is deprecated.