message: document why we have "badSafes"
diff: @@ -4,6 +4,10 @@ import { Safe, SafeOwner } from '../../generated/schema';
  import { toChecksumAddress, makeAccount } from '../utils';
  import { Address, ethereum, log } from '@graphprotocol/graph-ts';
  +// The following bad safe(s) are the confluence of this Gnosis issue:
  +// https://ethereum.stackexchange.com/questions/126648/call-reverts-when-asking-a-safe-for-its-owners-gnosis-chain
  +// and this graph protocol issue:
  +// https://github.com/graphprotocol/graph-node/issues/3487
  let badSafes = new Map<string, boolean>();
  badSafes.set('0x3af12EcC0A8Ef31cc935E0B25ea445249207d21A', true);
  