* call variables unambiguous things like `start_time` or `bst_date` to
reduce risk of passing in the wrong thing
* simplify the count_dict object - remove nested dict and start_date
fields as superfluous
* use static datetime objects in tests rather than calculating them
each time
Bumped notifications-utils to 3.7.0. Version 3.7.0 includes the
`convert_utc_to_bst` and `convert_bst_to_utc` functions and the
`LETTER_PROCESSING_DEADLINE` constant, so these have been removed from
this repo and anywhere using these has now been updated to get these
from `notifications-utils`.
Also bumped pytest by a patch version to bring in a bug fix.
specifically, all of the performance platform specific data layout now
happens in performance_platform_client.py - stuff like setting the
_timestamp, period etc, and the perf platform-specific nomenclature is
all handled there.
so that it doesn't appear generic when it's actually specific to
sending the daily notification totals. To do this, split it out into a
separate performance_platform directory, containing the business logic,
and make the performance_platform_client incredibly thin - all it
handles is adding ids to payloads, and sending stats.
Also, some changes to the config (not all done yet) since there is one
token per endpoint, not one for the whole platform as we'd previously
coded
