Fix versioning

[Pandapip1]

When trying to enable versioning, I was surprised to get the following error:

gavin@GAVIN-IDEAPAD-5A75N8AU:/mnt/c/Users/gavin/source/repos/py-s3fs$ s3cmd setversioning s3://gavins3fstesting enable

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    An unexpected error has occurred.
  Please try reproducing the error using
  the latest s3cmd code from the git master
  branch found at:
    https://github.com/s3tools/s3cmd
  and have a look at the known issues list:
    https://github.com/s3tools/s3cmd/wiki/Common-known-issues-and-their-solutions-(FAQ)
  If the error persists, please report the
  following lines (removing any private
  info as necessary) to:
   s3tools-bugs@lists.sourceforge.net


!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Invoked as: /home/gavin/bin/s3cmd setversioning s3://gavins3fstesting enable
Problem: <class 'NameError: name 'compute_content_md5' is not defined
S3cmd:   2.3.0-dev
python:   3.11.2 (main, Mar 13 2023, 12:18:29) [GCC 12.2.0]
environment LANG=en_US.UTF-8

Traceback (most recent call last):
  File "/home/gavin/bin/s3cmd", line 3461, in <module>
    rc = main()
         ^^^^^^
  File "/home/gavin/bin/s3cmd", line 3358, in main
    rc = cmd_func(args)
         ^^^^^^^^^^^^^^
  File "/home/gavin/bin/s3cmd", line 2211, in cmd_setversioning
    response = s3.set_versioning(bucket_uri, enabled)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/gavin/bin/s3cmdvenv/.venv/lib/python3.11/site-packages/S3/S3.py", line 1091, in set_versioning
    headers['content-md5'] = compute_content_md5(body)
                             ^^^^^^^^^^^^^^^^^^^
NameError: name 'compute_content_md5' is not defined

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    An unexpected error has occurred.
  Please try reproducing the error using
  the latest s3cmd code from the git master
  branch found at:
    https://github.com/s3tools/s3cmd
  and have a look at the known issues list:
    https://github.com/s3tools/s3cmd/wiki/Common-known-issues-and-their-solutions-(FAQ)
  If the error persists, please report the
  above lines (removing any private
  info as necessary) to:
   s3tools-bugs@lists.sourceforge.net
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

It looks like a function was renamed and one reference to the old name got left behind. This fixes it.

[fviard]

Thank you very much for your PR.
I don't know how I missed that, but it is a good catch.

fyi, I have "squashed" all your commits into a single one for merging your PR into master, as it looks like that the previous commit were simply different attempts without a real added value.
As a recommandation, for future PRs you could do here or in another project, it is usually a good practice to rework your set of commits to have a "clean history" of commits.
By that, I mean only having commit for changes sets that have an historical interest to be separated.
Usually, the cleanup can easily be performed using the "rebase interactive" feature of git.