[CI] Archive the release notes on version change

Summary:
This ensure that the release notes gets automatically archived and a new
fresh version created as soon as the software version changes from the
main CMakeLists.txt.

Depends on D7361.

Test Plan:

COMMIT_TYPE=archive-release-notes \
  ./contrib/source-control-tools/automated-commits.sh

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Subscribers: deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D7376