package/python-idna: bump to version 3.2

package/python-idna: bump to version 3.2

- Python 2 is not supported since version 3.0 so update all reverse
  dependencies and remove python-coherence
- License file name and its hash is updated due to:
  https://github.com/kjd/idna/commit/e7338bce90683246c480ddebd55b7682371389ed
  https://github.com/kjd/idna/commit/537aa99d4440b0f8a6178818350f27fcaab046ee

https://github.com/kjd/idna/blob/v3.2/HISTORY.rst

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>