message: Fix gc triggering
  Summary:
  Small bug in recent change to gc caused us to only have it at the
  beginning of a statement block rather than at each statement.
diff: @@ -338,7 +338,7 @@ impl Compiler<'_> {
  let is_statements = matches!(&stmt.node, Stmt::Statements(_));
  let res = self.stmt_direct(stmt, allow_gc);
  // No point inserting a GC point around statements, since they will contain inner statements we can do
  - if allow_gc && is_statements {
  + if allow_gc && !is_statements {
  // We could do this more efficiently by fusing the possible_gc
  // into the inner closure, but no real need - we insert allow_gc fairly rarely
  box move |eval| {
  