Fix index-state syntax

The second index-state stanza completely ovverides the first, resetting hackage index state to HEAD. See haskell/cabal#8568

Author: andreabedini

cabal.project

@@ -52,8 +52,8 @@ repository cardano-haskell-packages
 -- repeating the index-state for hackage to work around hackage.nix parsing limitation
 index-state: 2023-01-30T00:00:00Z
 index-state:
-  , hackage.haskell.org 2023-01-30T00:00:00Z
-  , cardano-haskell-packages 2022-12-14T00:40:15Z
+  , hackage.haskell.org 2022-09-27T00:00:00Z
+  , cardano-haskell-packages 2022-10-25T20:00:00Z
 
 -- with-compiler: ghc-8.10.7