[pkg] Run all unit tests in autopkgtest We previously forgot to copy `tox.ini` alongside the tests. As this file configures pytest pattern matching rules, we were not running quite a few tests. This is now fixed. The added tests required some adjustments in the Debian dependencies. Sadly, not all tests currently pass. It seems there are some ordering dependencies between the tests in regards to how data are loaded. Fixing this probably would probably be better debugged by ensuring the test suite does not fail when using pytest random-order plugin.

[pkg] Stop running unit tests from skeleton The test files shipped as part as the skeleton for `cubeweb-ctl newcube` are not meant to be run as part of our test suite!

[tests] Use 16 bytes key when testing Blowfish The version of Cryptodome currently in Debian only accepts Blowfish keys with at least 5 bytes. This is a bug (it should accept 4 as it did before) that has since been fixed upstream: https://github.com/Legrandin/pycryptodome/commit/93912230f3c39e09f4038cb17e301468687c6538 So we work around this issue by using a 16 bytes key instead (which happens to be the minimum recommended length).