Anton SC has a ligature problem

[davelab6]

Describe the bug

Anton SC has an ff ligature problem where the conversion of lowercase to small caps mishandled the ligature, so a lowercase ligature is substituted over two small-scaps fs.

To Reproduce

https://fonts.google.com/specimen/Anton+SC?preview.text=Waffles%20WAFFLES

Expected behavior

No ligature

Screenshots

@simoncozens might have insights

[simoncozens]

Looks like an issue with the order of lookups. The small cap rules are moved to the ccmp feature but they're in lookup 30; the liga feature is lookup 24. ccmp and liga are run in the same shaping "pause", so the rules are executed in order of lookup ID. This means the ligature happens first and the small caps afterwards. Our small-capifier should put the smcp rules into a fairly early lookup ID.

[vv-monsalve]

Repeated: This was reported by a user in #8331, in which Emma self-assigned her.