Function fetch_pinned 

pub async fn fetch_pinned(
    url: &str,
    sha256: &str,
    destination: &Path,
) -> Result<(), ManagedToolError>

Download url, verify it against the pinned sha256, and write it to destination atomically.

Errors

Returns ManagedToolError when the download fails, the checksum does not match the pinned value, or the file cannot be written.