[server] Add missing indices for undo support (closes #3259691) The tables used by the 'undo' feature were missing some indices, which among other things triggered repeated sequential scans when deleting old transactions.

usr/lib/PY_VERSION/*-packages/cubicweb/web
usr/share/cubicweb/cubes/shared/data
usr/share/cubicweb/cubes/shared/wdoc