Use a real deprecated version

Author: jneira

.github/workflows/test.yml

@@ -15,7 +15,7 @@ jobs:
         include:
           # To test a ghc version deprecated in newer hls versions
           - os: ubuntu-latest
-            ghc: 8.10.5
+            ghc: 8.10.4
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout