Resolve rubocop error

[athityakumar]

With the new version rollouts of rubocop-rspec gem in November, RSpec/ContextWording has been added. This enforces context descriptions to begin with 'when', 'with', or 'without'.

I think this makes sense for us to update the wordings as per this rule, as "with data from X data source" does seem more readable (IMO) than "reads data from X data source".