fix(`contract`): rm IntoFuture for CallBuilder #5833

Job	Run time
clippy	1m 51s
docs	2m 8s
doctest	3m 17s
feature-checks	9m 13s
fmt	13s
check no_std	57s
test ubuntu-latest stable --no-default-features	2m 57s
wasm-unknown	2m 59s
test ubuntu-latest stable	2m 46s
wasm-wasi	4m 33s
test ubuntu-latest stable --all-features	3m 16s
test ubuntu-latest nightly --no-default-features	2m 38s
test ubuntu-latest nightly	2m 36s
test ubuntu-latest nightly --all-features	2m 57s
test ubuntu-latest 1.81 --no-default-features	2m 5s
test ubuntu-latest 1.81	2m 4s
test windows-latest stable --no-default-features	8m 28s
test windows-latest stable	8m 23s
test windows-latest stable --all-features	8m 27s
test windows-latest nightly --no-default-features	7m 45s
test windows-latest nightly	8m 10s
test windows-latest nightly --all-features	7m 19s
test windows-latest 1.81 --no-default-features	4m 43s
test windows-latest 1.81	5m 30s
deny / cargo deny check	24s
ci success	1s
	1h 45m 40s

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