message: Prevent double clean up of ClientContext
diff: @@ -21,7 +21,7 @@ ClientContext::ClientContext(DuckDB &database)
  void ClientContext::Cleanup() {
  lock_guard<mutex> client_guard(context_lock);
  - if (is_invalidated) {
  + if (is_invalidated || !prepared_statements) {
  return;
  }
  if (transaction.HasActiveTransaction()) {
  @@ -30,8 +30,8 @@ void ClientContext::Cleanup() {
  transaction.Rollback();
  }
  }
  + assert(prepared_statements);
  db.transaction_manager.AddCatalogSet(*this, move(prepared_statements));
  -
  return CleanupInternal();
  }
  