Fix typo in helm-testing

Signed-off-by: Ivan Polchenko <[email protected]>

.github/workflows/on_push_main.yaml

@@ -31,6 +31,7 @@ jobs:
           changed=$(ct list-changed --target-branch ${{ github.event.repository.default_branch }})
           if [[ -n "$changed" ]]; then
             echo "changed=true" >> "$GITHUB_OUTPUT"
+          fi
 
   update_configs_repo:
     runs-on: ubuntu-latest