MDL-63619 tool_dataprivacy: Fix inheritance from parent contexts

MDL-63619 tool_dataprivacy: Fix inheritance from parent contexts

Inheritance should behave such that all contexts inherit from their
parent context.

Prior to this fix, if the value was not set on a context, then it was
getting a default of 'Inherit', but instead of inheritting from the
parent context, it was inheritting from its parent context _level_ which
is just wrong.