Fix the output of built-in iter() function example in Iterators (Section 9.8) of The Python Tutorial (GH-30110)

Updated the output for it=iter(s) from <iterator object at 0x00A1DB50> to <str_iterator object at 0x10c90e650>
(cherry picked from commit c5d18a5014f649368b5a4bca94e9ec7d2908b481)

Co-authored-by: Vivek Vashist <vivekvashist@gmail.com>