benchmarks CI updates - micro-benchmarks for "all stable features"; r… #821

Job	Run time
BoGo test suite	3m 48s
Run benchmarks	6m 53s
Validate external types appearing in public API	1m 14s
Build+test (stable, ubuntu-latest)	6m 50s
Build+test (stable, windows-latest)	13m 51s
Clippy (Nightly)	6m 24s
Clippy (strict / deny warnings)	4m 1s
Build+test (stable, macos-latest)	7m 1s
Measure coverage	9m 5s
Build+test (beta, ubuntu-latest)	6m 56s
Build+test (nightly, ubuntu-latest)	10m 0s
cross-target testing (armv7-linux-androideabi)	13m 59s
cross-target build with critical-section feature (thumbv6m-none-eabi)	1m 31s
cross-target build with critical-section feature (armv7-linux-androideabi)	1m 49s
Check for documentation errors	2m 10s
cross-target testing (i686-linux-android)	16m 53s
Features	4m 7s
cross-target testing (thumbv7neon-linux-androideabi)	14m 9s
Format	12s
cross-target testing (i586-unknown-linux-gnu)	4m 53s
Format (unstable)	20s
Smoke-test fuzzing targets	3m 26s
cross-target testing (i686-unknown-linux-gnu)	4m 10s
Check minimum versions of direct dependencies	35s
MSRV	1m 37s
cross-target testing (riscv64gc-unknown-linux-gnu)	11m 10s
Run openssl-tests	1m 58s
cross-target testing (s390x-unknown-linux-gnu)	13m 59s
Check semver compatibility	1m 2s
cross-target testing (aarch64-linux-android)	6m 3s
	3h 0m 6s

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