bench: deterministic rng and hashers; pin and shard the CodSpeed CI - #950

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

#### 🎉 Hooray! `codspeed-rust` just leveled up to 5.0.1!

A heads-up, this is a breaking change and it might affect your current performance baseline a bit. But here's the exciting part - it's packed with new, cool features and promises improved result stability 🥳!
Curious about what's new? Visit our releases page to delve into all the awesome details about this new version.

⚡ 2 improved benchmarks
✅ 186 untouched benchmarks

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	bench_unpad_message_ref	215.3 ns	165.3 ns	+30.25%
⚡	Simulation	send_and_receive[1]	1,169.1 µs	935.4 µs	+24.98%

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_{Comparing perf/bench-determinism (22a8bd5) with main (0ce4907)}