Merge pull request #8147 from erik-krogh/cacheReg

JS: cache RegExpCreationNode::getAReference

javascript/ql/lib/semmle/javascript/internal/CachedStages.qll

@@ -238,6 +238,8 @@ module Stages {
       1 = 1
       or
       DataFlow::SharedFlowStep::step(_, _)
+      or
+      exists(any(DataFlow::RegExpCreationNode e).getAReference())
     }
   }