add back change checking steps

.github/workflows/autogpt-infra-ci.yml

@@ -43,9 +43,14 @@ jobs:
         with:
           version: v3.14.4
 
-      - name: Set up chart-testing
-        uses: helm/chart-testing-action@v2.6.0
+      - name: Run chart-testing (list-changed)
+        id: list-changed
+        run: |
+          changed=$(ct list-changed --target-branch ${{ github.event.repository.default_branch }})
+          if [[ -n "$changed" ]]; then
+            echo "changed=true" >> "$GITHUB_OUTPUT"
+          fi
 
       - name: Run chart-testing (lint)
-        run: |
-          ct lint --target-branch master
+        if: steps.list-changed.outputs.changed == 'true'
+        run: ct lint --target-branch ${{ github.event.repository.default_branch }}