Only run haskell.yml when PR is not a draft

Author: fpringle

.github/workflows/haskell.yml

@@ -12,6 +12,11 @@ permissions:
 jobs:
   generate-matrix:
     name: "Generate matrix from cabal"
+    if: ( ( github.event_name == 'push' )
+        || ( github.event_name == 'pull_request'
+            && github.event.pull_request.draft == false
+           )
+        )
     outputs:
       matrix: ${{ steps.set-matrix.outputs.matrix }}
     runs-on: ubuntu-latest
@@ -25,7 +30,11 @@ jobs:
           version: 0.1.7.1
 
   test:
-
+    if: ( ( github.event_name == 'push' )
+        || ( github.event_name == 'pull_request'
+            && github.event.pull_request.draft == false
+           )
+        )
     name: ${{ matrix.ghc }} on ${{ matrix.os }}
     needs: generate-matrix
     runs-on: ${{ matrix.os }}