fix(testing): remove codspeed folder used for integration tests

[not-matthias]

Fixes #44

Since we're modifying the code for our custom Go runner, we need to properly fix the paths used in the URI. We already replaced _codspeed.go with _test.go, but we also have to remove the codspeed/ folder which is used for integration tests.

[Copilot]

Pull request overview

This PR introduces a utility function to remove the "codspeed" folder from file paths in the testing framework, improving the user experience by cleaning up file paths shown in test output and benchmark metadata. The change is part of handling integration tests that use codspeed benchmark files.

Key Changes:

• Added removeFolderFromPath() helper function to strip "codspeed" folder from file paths
• Applied folder removal in two contexts: callsite reporting and benchmark file tracking
• Imported strings package to support the new functionality

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
testing/testing/codspeed.go	Added new removeFolderFromPath function that strips specified folder names from paths by splitting on path separator
testing/testing/testing.go	Applied folder removal to callsite file paths when handling _codspeed.go files
testing/testing/benchmark.go	Applied folder removal to benchmark file paths when processing codspeed benchmark results

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[codspeed-hq]

CodSpeed Performance Report

Merging #45 will improve performances by 21.83%

_{Comparing cod-1811-incorrect-file-path-on-the-benchmark-result (bbc9ccc) with main (a88bf0f)}

Summary

⚡ 1 improvement
✅ 47 untouched
🆕 1 new

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	bench_collect_results[10000000, 25]	6.1 s	5 s	+21.83%
🆕	BenchmarkExternalFib	N/A	45 ns	N/A

[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.

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[adriencaccia]

LGTM, let's just make the benchmarks more relevant