Code cleanup: Remove TODO regarding optVNConstantPropOnJTrue removing…

… a tree twice. (#106976)

- The original issue (#10450) is closed as not reproducible becasue JIT no longer does any incremental ref count updates.

src/coreclr/jit/assertionprop.cpp

@@ -6484,9 +6484,6 @@ Compiler::fgWalkResult Compiler::optVNBasedFoldCurStmt(BasicBlock* block,
         return WALK_CONTINUE;
     }
 
-    // TODO https://github.com/dotnet/runtime/issues/10450:
-    // at that moment stmt could be already removed from the stmt list.
-
     optAssertionProp_Update(newTree, tree, stmt);
 
     JITDUMP("After VN-based fold of [%06u]:\n", tree->gtTreeID);