[devtools] qunit: use new assert APIs
test functions now accept an "assert" argument which exposes QUnit's
assert methods: assert.{expect,equal,deepEqual,ok}
Related to #5533333.
usr/lib/PY_VERSION/*-packages/cubicweb/server/
usr/lib/PY_VERSION/*-packages/cubicweb/hooks/
usr/lib/PY_VERSION/*-packages/cubicweb/sobjects/
usr/lib/PY_VERSION/*-packages/cubicweb/schemas/
usr/share/cubicweb/migration/