The function does waste gas as providing no value.
Manual review.
@external
def liquidate(collateral: address, user: address, debt_to_cover: uint256):
    assert debt_to_cover > 0, "DSCEngine__NeedsMoreThanZero"
    starting_user_health_factor: uint256 = self._health_factor(user)
    assert (
        starting_user_health_factor < MIN_HEALTH_FACTOR
    ), "DSCEngine__HealthFactorOk"
    token_amount_from_debt_covered: uint256 = self._get_token_amount_from_usd(
        collateral, debt_to_cover
    )
    bonus_collateral: uint256 = (
        token_amount_from_debt_covered * LIQUIDATION_BONUS
    ) // LIQUIDATION_PRECISION
    self._redeem_collateral(
        collateral,
        token_amount_from_debt_covered + bonus_collateral,
        user,
        msg.sender,
    )
    self._burn_dsc(debt_to_cover, user, msg.sender)
    ending_user_health_factor: uint256 = self._health_factor(user)
    assert (
        ending_user_health_factor > starting_user_health_factor
    ), "DSCEngine__HealthFactorNotImproved"
-    self._revert_if_health_factor_is_broken(msg.sender)