Generate bytes entry for table properties

[Stephen-Gates]

Desired Behaviour

Automatically set the value of the bytes property to the number of bytes used when the data package is exported.

This property should be set for each table in the data package.

This will help when uploading the data package to CKAN.

[Stephen-Gates]

I've added this to the set table properties acceptance test. It maybe better place in the Save file features. Feedback welcome.

[reminders[bot]]

:wave: @Stephen-Gates, update the acceptance test