docs: improve timeit autorange description

It not only determines but actually runs timeit a number of times. Also
be more concise; the original form said basically the same thing twice.

Co-authored-by: bkap123 <97006829+bkap123@users.noreply.github.com>

Author: scop

Doc/library/timeit.rst

@@ -145,13 +145,13 @@ The module defines three convenience functions and a public class:
 
    .. method:: Timer.autorange(callback=None, target_time=None)
 
-      Automatically determine how many times to call :meth:`.timeit`.
+      Call :meth:`.timeit` an automatically determined number of times.
 
-      This is a convenience function that calls :meth:`.timeit` repeatedly
-      so that the total time >= *Timer.target_time* seconds, returning the eventual
-      (number of loops, time taken for that number of loops). It calls
-      :meth:`.timeit` with increasing numbers from the sequence 1, 2, 5,
-      10, 20, 50, ... until the time taken is at least *target_time* seconds.
+      This is a convenience function that repeatedly calls :meth:`.timeit`
+      with an increasing amount of iterations from the sequence 1, 2, 5, 10,
+      20, 50, ... until the time taken is at least *target_time* seconds,
+      returning the eventual (number of loops, time taken for that number of
+      loops).
 
       If *callback* is given and is not ``None``, it will be called after
       each trial with two arguments: ``callback(number, time_taken)``.