fix reward distributor to bubble failures

in the simplest possible way, fix a bug which prevents reward
distribution from getting sent to L2 due to internal OOG gas logic in
optimism contract (normally if you are OOG then the remaining code in
RewardsDistribution would also fail, but optimism deliberately consumes
an excessive amount of gas in a way that causes only the internal call
to fail)

in accordance with [SIP-2036](https://sips-go29dg4x3-synthetixio.vercel.app/sips/sip-2036/)

note: if you are wondering why I didnt just call the rewards
distribution receiver contract normally and continue to be using hte low
level call, the reason is im trying to keep changes to a minimal and
this change basically ended up being a 1 line changes.

contracts/RewardsDistribution.sol

@@ -166,10 +166,13 @@ contract RewardsDistribution is Owned, IRewardsDistribution {
                 bytes memory payload = abi.encodeWithSignature("notifyRewardAmount(uint256)", distributions[i].amount);
 
                 // solhint-disable avoid-low-level-calls
-                (bool success, ) = distributions[i].destination.call(payload);
+                (bool success, bytes result) = distributions[i].destination.call(payload);
 
                 if (!success) {
-                    // Note: we're ignoring the return value as it will fail for contracts that do not implement RewardsDistributionRecipient.sol
+                    // if the error was emitted by the destination contract, bubble
+                    assembly {
+                        revert(add(result, 0x20), len)
+                    }
                 }
             }
         }