MBS-2349: Allow merging RGs when merging releases

[reosarevok]

Implement MBS-2349

Problem

We used to have a checkbox before NGS came which allowed editors to enter a merge for the associated release groups when merging releases, and I still don't know why it was removed. I think it's because ocharles thought it was better to just let orphaned RGs get autoremoved, but that goes against the whole merge rather than delete ethos.

Readding the checkbox would allow editors to stop leaving orphaned RGs behind, without them having to go merge them by hand separately (which is enough effort to often think "you know what, whatever, they'll be garbage-collected anyway").

Solution

This (re-)adds a checkbox "Also merge the associated release groups" when merging releases. If selected, a second "Merge release groups" edit will be entered when submitting the "Merge releases edit" (under the original editor's account since it's entered by their choice). Both edits are linked to each other by ModBot edit notes.

Testing

So far I've tested this manually and it does what we expect it to, so putting it up to see if the idea seems sensible to others.

Actions

• Write a test.
• Make the ModBot notes translatable (I guess? Although the credit edit notes when editing an artist name are not translatable).
• Figure out how to make these edits also appear on the "Thank you, your edit(s)" message, which they do not right now.

[reosarevok]

@brainzbot, retest this please

[mwiencek]

So far I've tested this manually and it does what we expect it to, so putting it up to see if the idea seems sensible to others.

It looks sensible to me. I tested it locally it seemed to work fine, too. But a test would be nice.

Make the ModBot notes translatable (I guess? Although the credit edit notes when editing an artist name are not translatable).

Yeah, it should use localized_note. I don't think we ever converted all the messages to use it.

Figure out how to make these edits also appear on the "Thank you, your edit(s)" message, which they do not right now.

You have to use _insert_edit for that, AFAIK.