pub fn flush(&mut self) -> anyhow::Result<()> {
        if let Some(patch) = self.patch.take() {
            self.inner.apply_patch(patch)?;
        }
        Ok(())
    }
Flushes changes from RAM to the wrapped database.

# Errors

Proxies database I/O errors.
core/lib/zk_os_merkle_tree/src/storage/mod.rs