perf: Nit fix to benchmarks

[cijothomas]

Some test were not run in benchmarks-CI due to missing feature flag.
Also did a nit cleanup - benchmarks didn't need rt-tokio so its cleaned up.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.1%. Comparing base (303803e) to head (549075d).
Report is 1 commits behind head on main.

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #2884   +/-   ##
=====================================
  Coverage   81.1%   81.1%           
=====================================
  Files        124     124           
  Lines      23927   23927           
=====================================
  Hits       19410   19410           
  Misses      4517    4517           

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[bantonsson]

I've done a more future proof fix for missing feature flags in #2885

[cijothomas]

I've done a more future proof fix for missing feature flags in #2885

❤️ Thanks!