fix: properly set output of changes check step in docs generation workflow

Author: omar-besbes

.github/workflows/generate-docs.yaml

@@ -35,7 +35,7 @@ jobs:
       - name: Check for changes in the directory
         id: check_changes
         run: |
-          git diff --exit-code solutions/${{ matrix.platform }} || echo "changes"
+          git diff --exit-code solutions/${{ matrix.platform }} || echo "changes" >> $GITHUB_OUTPUT
 
       - name: Commit and push changes
         if: steps.check_changes.outputs.changes == 'changes'