[3.13] pythongh-123789: secrets.randbits returns only non-negative int (pythonGH-123801) (python#123830)

pythongh-123789: `secrets.randbits` returns only non-negative int (pythonGH-123801)
(cherry picked from commit beee91c)

Co-authored-by: Wulian <[email protected]>

Author: miss-islington

Doc/library/secrets.rst

@@ -52,7 +52,7 @@ randomness that your operating system provides.
 
 .. function:: randbits(k)
 
-   Return an int with *k* random bits.
+   Return a non-negative int with *k* random bits.
 
 
 Generating tokens