update version to 36.3.1
update version to 36.3.1

change the in-code version to 36.3.1. The fact that this was forgotten
(rather: unknown to anyone involved), leads PyPI to incorrectly
announce the package version there to be still 36.2.0 while in fact it
is the new-and-shiny 36.3.0.

Signed-off-by: Andreas Lauser <429495c8e182c230dc2e2e45b7683abab22a535c@mbition.io>
Signed-off-by: Oliver Kopp <145f9cd3bd4b8f6f87f6a0c88db241a6cbaa88bd@mbition.io>

eerimoq/cantools,cantools/cantools