message: Remove obsolete Default implementation for Checksum
  Not needed anymore after
diff: @@ -9,8 +9,7 @@ use crate::errors::{make_cache_err, VmError};
  ///
  /// This is often referred to as "code ID" in go-cosmwasm, even if code ID
  /// usually refers to an auto-incrementing number.
  -#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash, Default)]
  -// Note: do not remove Default, we need it in go-cosmwasm (for now)
  +#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
  pub struct Checksum([u8; 32]);
  impl Checksum {
  