build: reduce futures dependencies #315

Job	Run time
run with single worker thread and deadlock detection	4m 58s
cargo manifest check	2m 20s
check build with madsim	1m 32s
run with address saniziter	6m 7s
misc check	9s
rust doc test (ubuntu-latest)	1m 53s
rust ffmt check (ubuntu-latest)	16s
rust machete check	52s
rust ffmt check (macos-latest)	16s
rust doc test (macos-latest)	2m 10s
rust ffmt check (windows-latest)	31s
rust doc test (windows-latest)	3m 32s
rust test with codecov (ubuntu-latest, stable)	9m 15s
rust ffmt check (ubuntu-24.04-arm)	11s
rust doc test (ubuntu-24.04-arm)	1m 29s
rust test with codecov (ubuntu-latest, 1.81.0)	7m 52s
rust udeps test (ubuntu-latest)	7m 0s
rust test with codecov (macos-latest, stable)	4m 44s
rust test with codecov (macos-latest, 1.81.0)	3m 33s
rust udeps test (macos-latest)	7m 5s
rust test with codecov (windows-latest, stable)	7m 52s
rust udeps test (windows-latest)	10m 0s
rust test with codecov (windows-latest, 1.81.0)	7m 38s
rust udeps test (ubuntu-24.04-arm)	6m 2s
rust test with codecov (ubuntu-24.04-arm, stable)	5m 41s
rust test with codecov (ubuntu-24.04-arm, 1.81.0)	4m 20s
	1h 47m 18s

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