add new step

.github/workflows/diff-quality.yml

@@ -41,4 +41,13 @@ jobs:
     - name: Checkout source branch and diff quality
       run:  |
         git checkout ${{ github.head_ref }}
-        diff-quality --violations=sqlfluff --compare-branch=origin/master --fail-under=95
+        diff-quality --violations=sqlfluff --compare-branch=origin/master --fail-under=95 > diff-quality-output.txt
+
+    - name: Check diff-quality output
+      run: | # the if is for cases diff quality tries to lint folders that are supposed to be ignored
+        if [ ! -s diff-quality-output.txt ]; then
+          echo "diff-quality output is empty. Success."
+        else
+          echo "Diff-quality:"
+          cat diff-quality-output.txt
+        fi