Migration to backfill LMSCourse.lms_api_course_id from existing grouping rows

[marcospri]

For:

• Store API IDs alongside LTI ones for users and courses #6880

While this data was in the database as part of Grouping.extra we "promoted" it to its own column on LMSCourse to make it easier to query and index.

While we only have this now for canvas now the new column names is a generic one now

See: #6944

Testing

• Launch a couple of assignment from different courses

https://hypothesis.instructure.com/courses/319/assignments/3308
https://hypothesis.instructure.com/courses/125/assignments/875

• Remove the ID set by the previous PR

in make sql

update lms_course set lms_api_course_id = null;

UPDATE 2

• Run the migration to backfill the values back:

tox -e dev --run-command 'alembic upgrade head'

• Check the values have been indeed set again:

in make sql:

select name, lms_api_course_id from lms_course where lms_api_course_id is not null;


                    name                     | lms_api_course_id 
---------------------------------------------+-------------------
 LTI 1.3 Testing                             | 319
 Developer Test Course with Sections Enabled | 125
(2 rows)

[mtomilov]

Looks good