.mint wont check if the recipient is able to receive the NFT. If an incorrect  address is passed, it will result in a silent failure and loss of asset.
OpenZeppelin recommendation is to use the safe variant of _mint.
Replace _mint() with _safeMint().
https://github.com/code-423n4/2022-12-tigris/blob/main/contracts/BondNFT.sol#L313
https://github.com/code-423n4/2022-12-tigris/blob/main/contracts/GovNFT.sol#L56
https://github.com/code-423n4/2022-12-tigris/blob/main/contracts/GovNFT.sol#L70
