Add ref

Author: alexfmpe

.github/workflows/haskell.yml

@@ -4,7 +4,7 @@ on: [push, pull_request]
 
 jobs:
   build:
-    uses: reflex-frp/reflex-community/.github/workflows/haskell.yml
+    uses: reflex-frp/reflex-community/.github/workflows/haskell.yml@0f9c2d9f01ed56ec4b324bcdf8e65f28ed9497e1
     with:
       matrix-ghc: "['8.4.4', '8.6.5', '8.8.4', '8.10.7', '9.0.1', '9.2.5', '9.4.5', '9.6.1', '9.8.2', '9.10.1']"
       matrix-os: "['ubuntu-latest', 'macos-latest']"