chore: update to noir 0.34.0

[olehmisar]

fixes 0.34.0 breaking changes. Also makes it work with aztec-nargo.

Had to move compute_chunks to a separate function because it fails to compile:

[noir_string_search] Testing test... error: Type annotation needed
    ┌─ src/lib.nr:209:48
    │
209 │         StringBody { body, chunks: StringBody::compute_chunks(body), byte_length: length }
    │                                                -------------- Could not determine type of generic argument
    │
    = Call stack:
      1. src/lib.nr:209:48

if someone needs for aztec-nargo today:

string_search = { tag = "v0.2.0", git = "https://github.com/olehmisar/noir_string_search/" }

[olehmisar]

@TomAFrench review please

[saleel]

👍
We can also update the version in Nargo.toml

[michaeljklein]

Please fix the unused import and Call to unconstrained function is unsafe warnings. Otherwise, LGTM

[TomAFrench]

Superceded by #5