Update GHC versions in the CI

Author: fendor

.github/workflows/test.yml

@@ -12,7 +12,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [macos-latest, ubuntu-latest, windows-latest]
-        ghc: [8.10.7, 9.4.7, 9.6.2, 9.8.2]
+        ghc: [8.10.7, 9.4.8, 9.6.4, 9.8.2]
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout
@@ -45,6 +45,9 @@ jobs:
           ghcup install ghc ${{ matrix.ghc }}
           ghcup set ghc ${{ matrix.ghc }}
 
+          # This is a prefetched, fallback HLS version.
+          # We want to make sure, we still support old GHC versions
+          # and graciously fallback to an HLS version that supports the old GHC version, such as 8.10.7
           ghcup install hls 2.2.0.0
           ghcup install hls latest
         shell: bash