fix some build warnings from ghc 9.4.6

It now notices that a RepoLocation may not be Local, in which case
pattern matching on Local wouldn't do.

However, in these cases, I think it always is a Local. In particular,
Git.Config.read is only run on local repos and upgrades LocalUnknown to
Local.

Git/CurrentRepo.hs

@@ -82,7 +82,9 @@ get = do
 		r <- Git.Config.read $ (newFrom loc)
 			{ gitDirSpecifiedExplicitly = True }
 		return $ if fromMaybe False (Git.Config.isBare r)
-			then r { location = (location r) { worktree = Nothing } }
+			then case location r of
+				loc'@(Local {}) -> r { location = loc' { worktree = Nothing } }
+				_ -> r
 			else r
 	configure Nothing Nothing = giveup "Not in a git repository."