[hadrian] stack.yaml out of sync with hadrian.cabal
Summary
Hadrian stack.yaml out of sync with it's hadrian.cabal.
I see that the Cabal file for Hadrian now requires happy-1.20.0 but the stack resolver lts-16.14 gives 1.19.12.
A possible resolution is to update hadrian/stack.yaml so:
extra-deps:
- happy-1.20.0
Steps to reproduce
I found this testing builds of ghc-lib against HEAD. I'm guessing that we don't have any stack/hadrian configs in CI.