Decoding with worker

[rootwarp]

Apply worker to apply multi-threading approach on decode process.

rootwarp@Mindhack2021 ~/g/d/dsrv-kzg-ceremony thread!? > mocha -g conversion

  conversion
Elapse Encode: 15.97098979100585 seconds
Elapse Decode: 0.31320316702127454 seconds
Elapse: Total 16.284192958027123 seconds
    ✔ naive (16291ms)
Decode Elapse: 9.59766529199481 seconds
Encode Elapse: 0.00012258300185203554 seconds
Total Elapse: 9.597787874996662 seconds
    ✔ worker (9895ms)

  2 passing (26s)

close #13