Bump `rand` & adapt tests to its API changes #1246

Job	Run time
cargo test (ubuntu-latest)	44s
cargo check (ubuntu-latest)	23s
cargo test (macOS-latest)	35s
Code Coverage (ubuntu-latest, unix)	1m 51s
cargo check (macOS-latest)	24s
cargo fmt --all -- --check	7s
cargo test (windows-latest)	2m 56s
cargo check (windows-latest)	2m 7s
Code Coverage (macos-latest, macos)	2m 21s
Code Coverage (windows-latest, windows)	4m 34s
	16m 2s

Provide feedback