Compilation error on newest Noir

[LogvinovLeon]

This library does not compile with the newest version of Noir:

error: The bit count in a bit-shift operation must fit in a u8, try casting the right hand side into a u8 first
   ┌─ /Users/artur/nargo/github.com/colinnielsen/noir-array-helpersv0.19.0/src/lib.nr:12:23
   │
12 │             value |= (arr_a[i*8+j] as u64) << ((56 - j*8) as u64);

[colinnielsen]

This should be fixed as of #16