Revert change to gen/haskell, but only install stack, not cabal

Author: domMayhew

.github/actions/setup-protoc-hololens/action.yml

@@ -7,7 +7,6 @@ runs:
     - name: Setup Haskell
       id: setup-hs
       uses: haskell-actions/setup@v2
-      working-directory: gen/haskell
       with:
         enable-stack: true
         stack-no-global: true