Update SHA3 Dependency

[itzmeanjan]

Update SHA3 dependency to latest commit itzmeanjan/sha3@2228e43.

This change increases time required for performing keygen, encaps and decaps. Considering Saber KEM implementation at commit 3628f5a as baseline while commit 1bf5a74 is contender implementation, we get 2-4% performance reduction.

Benchmark                           Time             CPU      Time Old      Time New       CPU Old       CPU New
----------------------------------------------------------------------------------------------------------------
lightsaber/keygen                +0.0453         +0.0453         40799         42647         40797         42644
lightsaber/encaps                +0.0313         +0.0313         60504         62400         60499         62395
lightsaber/decaps                +0.0228         +0.0228         77636         79408         77632         79402
saber/keygen                     +0.0314         +0.0314         87429         90178         87423         90172
saber/encaps                     +0.0346         +0.0347        116823        120867        116809        120857
saber/decaps                     +0.0223         +0.0223        142016        145187        142005        145178
firesaber/keygen                 +0.0281         +0.0281        154801        159151        154789        159137
firesaber/encaps                 +0.0239         +0.0239        193369        197989        193358        197978
firesaber/decaps                 +0.0201         +0.0201        227555        232126        227537        232109
OVERALL_GEOMEAN                  +0.0289         +0.0289             0             0             0             0