Downgrade haddock command

Author: maksbotan

.github/workflows/haskell-ci.yml

@@ -234,7 +234,7 @@ jobs:
           ${CABAL} -vnormal check
       - name: haddock
         run: |
-          $CABAL v2-haddock --disable-documentation --haddock-all $ARG_COMPILER --with-haddock $HADDOCK $ARG_TESTS $ARG_BENCH all
+          $CABAL v2-haddock $ARG_COMPILER --with-haddock $HADDOCK $ARG_TESTS $ARG_BENCH all
       - name: unconstrained build
         run: |
           rm -f cabal.project.local