[ADD] 14.0 base rest abstract attachment

[PierrickBrun]

based on #206

[sbidoul]

@qgroulard you may be interested in this one (for the images, maybe, or not)

[simahawk]

can't we name it only base_rest_attachment? I don't see the point of having "abstract" in the name :wink:

[PierrickBrun]

@simahawk You're right I've renamed the module.

Thanks for the review, I've made the changes, the tests still do not pass, I will need to look into it again to make it work

[PierrickBrun]

Also, I've used the same strategy as base_jsonifier to rename the module without breaking the installed databases so there is now and empty module inheriting the not empty one

[github-actions[bot]]

There hasn't been any activity on this pull request in the past 4 months, so it has been marked as stale and it will be closed automatically if no further activity occurs in the next 30 days. If you want this PR to never become stale, please ask a PSC member to apply the "no stale" label.

[simahawk]

@PierrickBrun shall we reopen this?