Update cabal file

hcat.cabal

@@ -24,7 +24,6 @@ library
   hs-source-dirs:
       src
   default-extensions:
-      GHC2021
       BlockArguments
       OverloadedStrings
   ghc-options: -Wall -Wunused-packages -fdefer-typed-holes
@@ -40,7 +39,6 @@ executable hcat
   hs-source-dirs:
       app
   default-extensions:
-      GHC2021
       BlockArguments
       OverloadedStrings
   ghc-options: -Wall -Wunused-packages -fdefer-typed-holes
@@ -59,7 +57,6 @@ test-suite spec
   hs-source-dirs:
       test
   default-extensions:
-      GHC2021
       BlockArguments
       OverloadedStrings
   ghc-options: -Wall -Wunused-packages -fdefer-typed-holes
@@ -74,4 +71,4 @@ test-suite spec
     , quickcheck-instances
     , quickcheck-text
     , text
-  default-language: Haskell2010
+  default-language: GHC2021

package.yaml

@@ -23,7 +23,6 @@ ghc-options:
   - -fdefer-typed-holes
 
 default-extensions:
-  - GHC2021
   - BlockArguments
   - OverloadedStrings
 
@@ -54,3 +53,5 @@ tests:
       - quickcheck-instances
       - quickcheck-text
     build-tools: hspec-discover
+    verbatim:
+      default-language: GHC2021