Byline and Credit fields not using asciifolding

Hello,

See related https://github.com/guardian/grid/pull/1246. Usefully, one can search for "walesa" and find "wałęsa" (and _vice versa_) when the term is a part of the Description field.

Unfortunately, both Byline and Credit fields aren't working that way. Please compare:
https://[PROD]/search?query=donovan by:"Pål Hansen"
&
https://[PROD]/search?query=donovan by:"Pal Hansen"

Having ES asciifolding working for these two fields is more important than for Description and is a prerequisite to fixing inconsistencies and misspellings of photographer's names. But yes, we also need a way to opt out of this future default behaviour and search like today.

Regards
Mateusz