Mitigation Confirmed for M-03

[code423n4]

The issue raised in M-03 was that the oracle feed wasn't validated to confirm that the data was fresh. To mitigate this, _stalenessThreshold was added. If block.timestamp - updatedAt > _stalenessThreshold (i.e. the data wasn't update recently enough) then getRate will revert disallowing use until fresher data is published.

[c4-judge]

GalloDaSballo marked the issue as satisfactory