[Fix] Add version number back to the doc by rflamary · Pull Request #696 · PythonOT/POT

Types of changes

This PR adds the version number in the documentation since it was removed because of the update of rtd theme.

We now have this:
image

Motivation and context / Related issue

How has this been tested (if it applies)

PR checklist

  • I have read the CONTRIBUTING document.
  • The documentation is up-to-date with the changes I made (check build artifacts).
  • All tests passed, and additional code has been covered with new tests.
  • I have added the PR and Issue fix to the RELEASES.md file.