Bump Python version to 3.8 because nowadays Python 3.8 is the default
Python version delivered in many Linux distributions. Publish new
sdlpy version 3.1.1 due to Python version bump.
Issue-Id: RIC-923
Signed-off-by: Timo Tietavainen <timo.tietavainen@nokia.com>
Change-Id: Ia05c18456319fed82edb9dac0bc2bf7a9be8cf49