[web] Have the LoginController return 403 on failed auth (closes #11569950)

[devtools] Drop old init_test_database backward compat

[devtools] show DeprecationWarning during test execution They are not shown by default since python 2.7

[devtools] deprecate usage of sources file for test This is old support which clutters the code and should no more be used. As this is rarely used (if it is) and test only, it feels ok to drop support at once without a deprecation phase.

[devtools] Set dumb value for postgres's db-host to avoid unexpected connection to a local server Currently, if something goes wrong (eg config built before call to startpgcluster) while a pg server is running on localhost, it may connect to this server and run the test in there unexepectedly.

[ldapfeed] ldap3 do not raise an exception in case of failure of cnx.bind() but return 'False' instead.

[test] add a test to ensure we get an AuthenticationError with ldapfeed when using (correct login, wrong password) credentials

[entity] Exclude computed relations from Entity.copy_relations Closes #12481591.

[pkg] Set version to 3.22.2.dev0 So that cubes used in test dependencies do not install a released CubicWeb.

[devtools] pep8 a bit package's __init__