fix: use proper iterations times and fix round sizes

[art049]

• fix: use time per iteration instead of total round time in stats
• feat: increase the min round time to a bigger value (+/- 1ms)

[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #67 will improve performances by 3.05%

_{Comparing cod-505-use-correct-timings-in-pytest-codspeed-walltime (bec227d) with master (003c3b4)}

Summary

⚡ 1 improvements
✅ 46 untouched benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	test_combination_lists[5-4]	28.7 µs	27.9 µs	+3.05%

[codspeed-hq]

CodSpeed Walltime Performance Report

Merging #67 will degrade performances by 5%

_{Comparing cod-505-use-correct-timings-in-pytest-codspeed-walltime (bec227d) with master (003c3b4)}

Summary

⚡ 33 improvements
❌ 1 regressions
✅ 13 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	test_iir_filter_process	3 µs	2.7 µs	+9.89%
⚡	test_iir_filter_set_coefficients[a_coeffs0-b_coeffs0]	852 ns	617.9 ns	+37.89%
⚡	test_make_allpass	5.2 µs	4.7 µs	+10.63%
⚡	test_make_bandpass	5.5 µs	4.9 µs	+11.15%
⚡	test_make_highpass	5.7 µs	5 µs	+13.52%
⚡	test_make_highshelf	7.4 µs	6.6 µs	+12.06%
⚡	test_make_lowpass	5.7 µs	4.9 µs	+15.17%
⚡	test_make_lowshelf	7.2 µs	6.5 µs	+11.52%
⚡	test_make_peak	6.4 µs	5.7 µs	+13.24%
⚡	test_color[graph0-3]	27.1 µs	25.7 µs	+5.54%
⚡	test_combination_lists[0-0]	1.9 µs	1.5 µs	+28.36%
⚡	test_combination_lists[4-2]	3.6 µs	3.3 µs	+10%
⚡	test_combination_lists[5-4]	3.4 µs	3 µs	+12.94%
⚡	test_generate_all_combinations[0-0]	1,212 ns	867.7 ns	+39.68%
⚡	test_generate_all_combinations[4-2]	5.9 µs	5.6 µs	+5.88%
⚡	test_generate_parenthesis[3]	7.8 µs	7.4 µs	+4.87%
⚡	test_get_valid_pos[pos0-4]	2.8 µs	2.5 µs	+16.02%
⚡	test_hamilton_cycle[graph0]	23.9 µs	23.2 µs	+2.76%
⚡	test_is_complete[board0]	1.8 µs	1.3 µs	+35.16%
⚡	test_is_safe[board0-1-1]	10.1 µs	9.3 µs	+8.72%
...	...	...	...	...

ℹ️ Only the first 20 benchmarks are displayed. Go to the app to view all benchmarks.

[adriencaccia]

Let's merge #65 before this one, so that the reports will work correctly