Edc

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- update tests

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- update test models

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- handle a number of regressions
- consolidate model managers and managers on model mixins
to make it easier to predict the _default_manager. Users
should add unitests to confirm concrete model classes
have the expected _default_manager (all with model mixins)
- floor sec/microsec on datetimes when comparing in form
and form-validator validation (edc-appointment
edc-visit-schedule, edc-visit-tracking, edc-crf)
- remove `SiteModelMixin` from default on/off schedule
model mixins. Add this mixin manually to the concrete
class.

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- add related visit methods to historical model (edc-model)
- minor fixes to off/on schedule models

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- added base method to access offschedule_datetime, typing (edc-crf)
- removed features/fields that create `next refill` on submission of
study medication report (edc-pharmacy)
- trivial (edc-protocol-incident)
- fixed issue that incorrectly compares int to str when confirming
that the grade from the user matches the grade from the evaluator
(edc-reportable)

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- rename module edc-protocol-deviation to edc-protocol-incident. This
requires manually renaming tables to reflect the app name and updating
the django_migration table app column with the new app name. Migrations
have been squashed for future users (edc-protocol-incident)
- deprecate path form_validator_mixin for form_validator_mixins
(edc-form-validator)