Function writable

fendermint/storage/src/im.rs:285–288

(data: TestData)

    #[quickcheck]
    fn writable(data: TestData) -> bool {
        let backend = InMemoryBackend::<TestKVStore>::default();
        check_writable(&backend, data)
    }

    #[quickcheck]
    fn write_isolation(data: TestDataMulti<2>) -> bool {