scrypt: Increase log_n until it is measurable

[str4d]

Closes #418.

[str4d]

@Rileran could you test this and check that it resolves your issue?

[codecov]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

Comparison is base (ed12d5f) 41.56% compared to head (967750c) 41.51%.
Report is 2 commits behind head on main.

Files	Patch %	Lines
age/src/scrypt.rs	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #424      +/-   ##
==========================================
- Coverage   41.56%   41.51%   -0.06%     
==========================================
  Files          34       34              
  Lines        3214     3218       +4     
==========================================
  Hits         1336     1336              
- Misses       1878     1882       +4     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[Rileran]

Works great, thanks for the quick fix !