Fix elem.drop interpretation (#7668)

Don't drop the segment in the module as the module can be used again
later.

Instead add the segment to the dropped segments set.

Fixes the fuzzing issue described in
#7658 (comment).

Author: osa1

src/wasm-interpreter.h

@@ -3654,9 +3654,8 @@ class ModuleRunnerBase : public ExpressionRunner<SubType> {
   }
 
   Flow visitElemDrop(ElemDrop* curr) {
-    Module& wasm = *self()->getModule();
     ElementSegment* seg = wasm.getElementSegment(curr->segment);
-    seg->data.clear();
+    droppedElementSegments.insert(seg->name);
     return {};
   }