cubicweb #4901150 computed relation types are not loaded from the database [validation pending]

computed relation type are properly serialized but are not loaded at all.

priorityimportant
typebug
done in3.20.4
load1.000
load left0.000
closed by#cc4b8021bdf3 [schemaserial] fix detection of CWComputedRType table, closes #4901150
patch[schemaserial] fix detection of CWComputedRType table, closes #4901150 [applied]