CI: Install upcoming CFFI 1.17.0 for Python 3.13 compatibility

Workaround-For: python-cffi/cffi#71

Author: chrysn

.gitlab-ci.yml

@@ -69,6 +69,8 @@ test:3.13:
     - source ~/.cargo/env
     - rm -f .coverage* collected-coverage
     - pip install tox
+    # Workaround for https://github.com/python-cffi/cffi/issues/71
+    - tox -e py313-allextras exec --skip-pkg-install -- pip install git+https://github.com/python-cffi/cffi/
     # Separate run so I don't waste time telling errors in setup apart from errors at runtime
     - tox --notest --skip-env '^py31[^3]'
     - "AIOCOAP_TEST_MCIF=\"$(ip -j -6 route list default | python3 -c 'import sys, json; print(json.load(sys.stdin)[0][\"dev\"])')\" tox --skip-env '^py31[^3]'"