[MC-1439][MC-1474] fix(curated-recommendations): fix topic and receivedRank

References

MC-1439: As a workaround, we agreed with Firefox FE (Scott) that we will not emit topics for markets other than New Tab en-US, because we are not confident topic labels are localized correctly in Fx130, and we only need to experiment with them in English locales. I believe there was a concern about feature whiplash if this were to be solved in Nimbus through audience targeting, and that the underlying issue causing feature whiplash has been solved starting from Fx131. (But I have to admit it's a bit out of my wheelhouse.)
MC-1474: receivedRank must be 0, 1, 2, ... in the response. This was a bug.

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