cubicweb #2742462 drop typed_eid in favour of int [validation pending]

typed_eid was introduced to abstract the eid type when running on Google AppEngine. It is not used anymore and can be removed.

prioritynormal
typeenhancement
appeared in<not specified>
done in3.17.0
load0.100
load left0.000
closed by#8875:f5027f8d2478
patchdrop typed_eid() in favour of int() (closes #2742462) [applied]