merge with 3.21.3 The change in unittest_serverctl.py is needed because of daef7ce08fea (from 3.20.11) and 3914388b2d0f (from the 3.22 branch). Due to both changes, CubicWebTC.config.repository no longer creates a new repository (and thus, a new connection). Since both DBDumpCommand and CubicWebTC.tearDown try to shutdown the repo, tearDown breaks apart. The solution is to temporarily disable ServerConfiguration's config cache. By forcing DBDumpCommand to get a new configuration object, it then gets its own Repo object, allowing tearDown and DBDumpCommand to work independently.

if repo.system_source.dbdriver == 'postgres':
    sql('ALTER TABLE appears ADD COLUMN weight float')
    sql('UPDATE appears SET weight=1.0 ')