Update helm/chart-testing-action action to v2.7.0

Author: renovate[bot]

.github/workflows/ci.yaml

@@ -21,7 +21,7 @@ jobs:
           python-version: "3.10"
 
       - name: Set up chart-testing
-        uses: helm/chart-testing-action@v2.6.1
+        uses: helm/chart-testing-action@v2.7.0
 
       - name: Run chart-testing (lint)
         run: ct lint --config ct.yaml