Break out config file types

[jonrohan]

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: f15fe7df33e25ccd5075b6cd0e38901a09bcd94d

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@primer/stylelint-config	Minor

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[jonrohan]

Cool 😍 do you want me to test this against dotcom, or did you already give it a go?

I already tested in dotcom, going to test in PVC and PCSS also