cubicweb #2789089 facet dom id are not valid jQuery identifier [done]

they include facet.__regid__ without ensuring it doesn't contain special jquery characters.

prioritynormal
typebug
done in3.15.11
load0.100
load left0.000
closed by#6ed22ac7257c [facet] ensure a facet DOM id is a valid jQuery identifier. Closes #2789089
patch[facet]?ensure a facet DOM id is a valid jQuery identifier [applied]