GHA: use ghc-9.6.6 & cabal-3.14

Author: coot

.github/workflows/haskell.yml

@@ -11,7 +11,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ghc: ["9.6", "9.8", "9.10", "9.12"]
+        ghc: ["9.6.6", "9.8", "9.10", "9.12"]
         os: [ubuntu-latest, macos-latest, windows-latest]
 
     defaults:
@@ -27,7 +27,7 @@ jobs:
       id: setup-haskell
       with:
         ghc-version: ${{ matrix.ghc }}
-        cabal-version: "3.12.1.0"
+        cabal-version: "3.14.2.0"
 
     - name: Install LLVM (macOS)
       if: runner.os == 'macOS' && matrix.ghc == '8.10'