Unclutter ormolu script

[fisx]

Checklist

• Add a new entry in an appropriate subdirectory of changelog.d
• Read and follow the PR guidelines

[fisx]

$ git grep -Hn package-defaults.yaml | grep -v ^changelog.d/5-internal/unclutter-ormolu-script
libs/wire-api/test/golden/gentests.sh:183:readarray -t EXTS < <(sed -rn '/^default-extensions:/,$ { s/^- (.*)/\1/ }' ../../package-defaults.yaml)

I don't think we'll ever be able to call this script again without heavy rewriting work, so I think this is fine?