_release_notes.toml formatting does not have standard formatting

[alice-i-cecile]

This creates nasty diffs during format-on-save.

Missing spaces.

Line breaks.

[IceSentry]

I think the easiest thing to do would be to make sure to save the file with a formatter before opening the first PR. We can add the spaces for the list, but the newlines on longer list I don't really know what the heuristic would be for that.

[IceSentry]

oh, but that file is regenerated every time, right....

[rparrett]

Does the toml crate's pretty serialization match the expected format?

I'll try to remember to look into that at some point.