Attempting to fix file uploads without upgrading to 6.1

[drusepth]

Grabbing what I can from rails app:update while still on 6.0.3.4 to try to fix file uploads until we can close #893.

ActiveRecord::NotNullViolation: PG::NotNullViolation: ERROR: null value in column "service_name" violates not-null constraintDETAIL: Failing row contains (30984, qlf91kjkir1lihmhmdqlf4ck5cfl, image.gif, image/gif, {"identified":true}, 9302, n+77QWYvQ/JeXG5rrUyN1w==, 2021-08-27 07:31:44.978173, null).

Probably need to double-check this diff (rough merge), but it doesn't seem to even solve the problem so it's mostly just a push-for-the-progress WIP to work from.

FWIW, this seems to only affect user avatar uploads (which use ActiveStorage's has_one_attached) and not image uploads to notebook pages (which use paperclip's has_attached_file).

[drusepth]

These migrations have both been run in prod; didn't seem to have an effect on ActiveStorage's errors though.

[drusepth]

This was fixed with #1016 and a dupe of many of the changes in #893. Closing without merge.