CODEOWNERS detection order is incorrect

[heaths]

go-codeowners/codeowners.go

Line 54 in 01f12d1

for _, p := range []string{".", "docs", ".github", ".gitlab"} {

I happened to notice this while looking into fixing #43: according to https://docs.github.com/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/about-code-owners#codeowners-file-location the order is wrong. It should check for a CODEOWNERS file in .github/ (and presumably .gitlab/) first, then the root, then under docs/.

For most repos this likely won't matter since they probably only have a single CODEOWNERS file anyway, but matching the documented order could matter for some.