Document GHC-58427

[Bodigrim]

Occurs in the wild. From alexwl/haskell-code-explorer#52:

2025-10-14 15:22:52.158591 CST : [error] Error while indexing HaskellModulePath {getHaskellModulePath = "/Users/liuzichao/hakyll/lib/Hakyll.hs"} : /Users/liuzichao/hakyll/lib/Hakyll.hs:56:1: error: [GHC-58427]
    attempting to use module `main:Hakyll.Web.Feed' (/Users/liuzichao/hakyll/lib/Hakyll/Web/Feed.hs) which is not loaded