chore(deps): update helm release promtail to v6.16.6

| datasource | package  | from   | to     |
| ---------- | -------- | ------ | ------ |
| helm       | promtail | 6.15.3 | 6.16.6 |

src/promtail/zarf.yaml

@@ -11,7 +11,7 @@ components:
     charts:
       - name: promtail
         url: https://grafana.github.io/helm-charts/
-        version: 6.15.3
+        version: 6.16.6
         namespace: promtail
         gitPath: charts/promtail
         valuesFiles: