upgrade to GHC 9.4.8

stack.yaml

-resolver: lts-18.24
+resolver: lts-21.25
 pvp-bounds: both
 ghc-options:
     $locals: -j2

stack.yaml.lock

@@ -3,10 +3,10 @@
 # For more information, please see the documentation at:
 #   https://docs.haskellstack.org/en/stable/lock_files
 
-snapshots:
-- original: lts-18.24
-  completed:
-    sha256: 06d844ba51e49907bd29cb58b4a5f86ee7587a4cd7e6cf395eeec16cba619ce8
-    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/18/24.yaml
-    size: 587821
 packages: []
+snapshots:
+- completed:
+    sha256: a81fb3877c4f9031e1325eb3935122e608d80715dc16b586eb11ddbff8671ecd
+    size: 640086
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/21/25.yaml
+  original: lts-21.25

sv2v.cabal

@@ -129,6 +129,7 @@ executable sv2v
     "-with-rtsopts=-N -A32m"
     -funbox-strict-fields
     -Wall
+    -Wno-incomplete-uni-patterns
 
 source-repository head
   type:     git