cubicweb-fastimport #4835633 Memory leak [done]

After a few thousands lines imported, and despite calling cnx.clear(), the memory consumption jumps to several gigabytes.

The responsible is session.user that has its relation_cache filled with all the imported entities (because it owns them).

Workaround, add "cnx.user._cw_related_cache.clear()" after each call to the FlushController.

done in0.3.0
load left0.000
closed by#ea8f2de8e39e Avoid a memory leak
patchEntities: do not update the rel cache for cnx.user [applied]Entities: fix a potential NameError [rejected]Avoid a memory leak [applied]