Clean up exec stdout

[GuillaumeLagrange]

New output

$ codspeed exec --warmup-time 2s --max-time 2s -- sleep 1                                                      130 ↵

►►► Running the benchmarks
Sudo privileges are required to continue.
Place your finger on the fingerprint reader
Executing: sleep 1
Completed 2 warmup rounds
Warmup done, now performing 2 rounds

►►► Uploading results
Linked repository: GuillaumeLagrange/small-programs
Performance data uploaded

►►► Benchmark results

sleep 1: 1.01 s

To see the full report, visit: https://codspeed.io/GuillaumeLagrange/small-programs/runs/697370a556d771e08525ca15

[codspeed-hq]

Merging this PR will not alter performance

✅ 4 untouched benchmarks

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_{Comparing clean-up-exec-stdout (7795ca3) with main (2d3ea9a)}