fix(upload): label dropped benchmarks in the comparison table

[adriencaccia]

The comparison table labeled each row by its category, so a benchmark the base run measured and the head run did not printed as "Regression" with - values. Rows with the Missing status now print as "Dropped".

[codspeed]

Merging this PR will not alter performance

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

✅ 31 untouched benchmarks
⏩ 6 skipped benchmarks¹

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_{Comparing fix/show-dropped-benchmarks-in-comparison-table (701b0a7) with main (8c603c2)}

Footnotes

1. 6 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩