fix(lint): allow readonly modifier on indexParameter in useNamingConvention

[sepruko]

Summary

Does not change any defaults, and adds a changelog entry. Closes #4277.

Test Plan

Updated snapshots to include readonly index signatures.

[codspeed-hq]

CodSpeed Performance Report

Merging #4286 will degrade performances by 22.18%

_{Comparing sepruko:fix/use-naming-convention-readonly-index-param (0f3056c) with main (7bab172)}

Summary

⚡ 1 improvements
❌ 1 regressions
✅ 103 untouched benchmarks

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

Benchmarks breakdown

	Benchmark	main	sepruko:fix/use-naming-convention-readonly-index-param	Change
❌	big5-added_15586211152145260264.json[cached]	437.2 µs	561.8 µs	-22.18%
⚡	db_17847247775464589309.json[cached]	13.8 ms	12.8 ms	+7.85%

[Conaclos]

Looks good to me! Unfortunately, you accidentally formatted the CHANGELOG. This is causing a lot of unwanted changes. Could you please fix this?

[sepruko]

Looks good to me! Unfortunately, you accidentally formatted the CHANGELOG. This is causing a lot of unwanted changes. Could you please fix this?

Oops! I was wondering why the PR diff was so large... All fixed now.