CI: Add test to ensure schema migrations are complete

Author: erikd

.github/workflows/haskell.yml

@@ -107,7 +107,7 @@ jobs:
     - uses: actions/cache@v3
       name: Cache cabal store
       with:
-        path: | 
+        path: |
           ${{ steps.setup-haskell.outputs.cabal-store }}
           dist-newstyle
         key: cache-cabal-store-v1-${{ runner.os }}-${{ matrix.ghc }}-${{ hashFiles('dependencies.txt') }}
@@ -144,3 +144,15 @@ jobs:
 
     - name: Run tests
       run: cabal test all -j1
+
+    - name: Check that Schema Migrations are complete
+      id: schema_check
+      run: |
+        PGPASSFILE=config/pgpass-mainnet cabal run cardano-db-tool -- run-migrations --mdir schema/ --ldir /tmp/
+        git diff schema/ > schema.diff
+        line_count="$(wc -l schema.diff)"
+        if test $(line_count} > 0 ; then
+          echo "Schema diff"
+          cat schema.diff
+          exit 1
+          fi