Use HexFormat to print out byte[] properties

We are currently using Arrays.toString(byte[]) to format these, which is verbose and not useful for the typical case of binary data, where having unsigned values is much more obvious.

Once we have Java 17's HexFormat at our disposal, use its formatting capabilities to emit reasonably-formatted arrays of hex.

Note we already have an encoding utility available in MD-SAL (in ietf-type-util), hence this is also up for consideration for mdsal-9.0.0.