Ensure that Hop complies with ASF encryption policy

Ensure that Hop complies with ASF encryption policy. See encryption policy.

I don't know whether Hop already includes encryption technology, but it's possible that HOP-2345 and/or HOP-2465 will, since they use AES.

If Hop uses encryption technology, there are steps that we need to take before the code lands on ASF servers (e.g. committed to git), not just on the next Hop release.