Rust

xtask: fix nixfmt + update Nix flake + fix CI #6525

Job	Run time
Integration Test (x86_64)	1m 30s
Integration Test (AArch64)	1m 15s
Integration Test (x86_64 Windows)	4m 33s
Integration Test (IA-32)	1m 26s
Unit + Doc Tests (Miri)	1m 11s
Nightly (build, test, doc)	1m 37s
Unit + Doc Tests	50s
Build (uefi-raw MSRV)	36s
Build Standard Binary (nightly)	31s
Build (stable MSRV)	39s
Build (feature permutations)	3m 56s
Test Coverage	46s
	18m 50s

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