perf(bench): Used iter_batched to clone widgets in setup function

[Valentin271]

Replaced Bencher::iter by Bencher::iter_batched to clone the widget in the setup function instead of in the benchmark timing.

See this PR for more information about iter_batched and its use.

See #262 for the original paragraph implementation.
See #368 for the original block implementation.

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New benches reports

Block didn't really move, times were so low in the first place.
Paragraph saw increases of ~20% for 2048 lines and ~65% for 65000 lines. (new is still very high but its only copying memory, not much we can do ..., maybe we should remove it too?)

Block

Paragraph

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PS : Not sure about the conventional commit type, feel free to edit

[codecov]

Codecov Report

Merging #383 (013d510) into main (e18393d) will increase coverage by 0.02%.
Report is 4 commits behind head on main.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #383      +/-   ##
==========================================
+ Coverage   84.99%   85.02%   +0.02%     
==========================================
  Files          40       40              
  Lines        8686     8683       -3     
==========================================
  Hits         7383     7383              
+ Misses       1303     1300       -3     

see 2 files with indirect coverage changes

[joshka]

Thanks. LGTM