change of etcd.image.registry triggers ERROR

If you change value `etcd.image.registry` (into ie.: local proxy) you'll get following error:

```shell
Error: execution error at (apisix/charts/etcd/templates/NOTES.txt:124:4):

⚠ ERROR: Original containers have been substituted for unrecognized ones. Deploying this chart with non-standard containers is likely to cause degraded security and performance, broken chart features, and missing environment variables.

Unrecognized images:
- /bitnamilegacy/etcd:latest

If you are sure you want to proceed with non-standard containers, you can skip container image verification by setting the global parameter 'global.security.allowInsecureImages' to true.
Further information can be obtained at https://github.com/bitnami/charts/issues/30850
```

Start by reading apisix/charts/etcd/templates/NOTES.txt around line 124 and reproduce the failure after changing etcd.image.registry to a local proxy. Trace the chart's image verification behavior and confirm that a registry override can be deployed without the reported error, while preserving the intended security checks.

Written by the indexing model from the issue text.