message: fix: check signature is_valid before m_of_n_verify
diff: @@ -28,7 +28,14 @@ impl Verifier {
  .signatures
  .iter()
  .filter_map(|sig_data| match Signature::from_slice(sig_data) {
  - Ok(sig) => Some(sig),
  + Ok(sig) => {
  + if sig.is_valid() {
  + Some(sig)
  + } else {
  + debug!("invalid signature: {:?}", sig);
  + None
  + }
  + }
  Err(err) => {
  debug!("signature error: {}", err);
  None
  