Support in Java client for publishing columns of type byte[]

[ilyaberdnikov]

As a user of the Java client, I want to be able to publish variable-length byte arrays into a Deephaven table column. Currently attempting to publish

ColumnHeader<byte[]> binary = ColumnHeader.of("B", byte[].class)

throws an exception from here

However, since Arrow supports VarBinaryVector, it might be possible to implement this in the same way that publishing a String-valued column is currently published.

[ilyaberdnikov]

I've taken a stab at it here: #4507 @devinrsmith @nbauernfeind, perhaps this could help somehow?