Log exception from poll.processMessage()

[yuetloo]

Prerequisites

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• I checked to make sure that this request has not already been filed

Motivation

If the exception from poll.processMessage() is logged when the quiet flag is off, it will help debugging.

https://github.com/privacy-scaling-explorations/maci/blob/dev/core/ts/Poll.ts#L326-L333

    } catch (e) {
      if (e instanceof ProcessMessageError) {
        throw e;
      } else {
        throw new ProcessMessageError(ProcessMessageErrors.FailedDecryption);
      }
    }
  };

Details

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