cubicweb #2410507 MemoryError with db-rebuild-fti [validation pending]

cubicweb-ctl db-rebuild-fti builds a lot of entities but never drops session's cache. This can lead to MemoryError on big databases.

prioritynormal
typebug
done in3.15.2
load0.250
load left0.000
closed by#4fb20c09017a [fti] drop entity cache once an etype is indexed (closes #2410507)