Update rdoc dependency specification to ~> 3.9
Update rdoc dependency specification to ~> 3.9

b-dean/thor,groovenauts/thor,fhernandez173/thor,segiddins/thor,flyinbutrs/thor,linkodehub/thor,doudou/thor,flyinbutrs/thor,shaiguitar/thor,r7kamura/thor,r7kamura/thor,segiddins/thor,sideci-sample/sideci-sample-thor,groovenauts/thor,linkodehub/thor,fhernandez173/thor,fancyremarker/thor,b-dean/thor,sideci-sample/sideci-sample-thor,erikhuda/thor,fancyremarker/thor