Magma EnableHistoryCompaction will clear history from 7.2 on full compaction

From reading of the code, once we enable the EnableHistoryCompaction, if one does a full compaction, it will clear away all history present in 7.2 data. This is because 7.2 data doesn't have per doc history enabled/disabled flag and so all docs are treated as not having history enabled, even though they are part of the history window. The bitfield added in ValueFormat, will always be 0 in Neo, even for docs that are inside of the history window.

This is not the desired behaviour and wasn't the behaviour in 7.2 (where we would retain history even if a full compaction is done).