chore(helm): update image docker.io/nginxinc/nginx-unprivileged digest to 502f1c3 (#37961)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
|
[docker.io/nginxinc/nginx-unprivileged](https://redirect.github.com/nginx/docker-nginx-unprivileged)
| digest | `1e1d77c` -> `502f1c3` |

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charts/premium/nextcloud/values.yaml

@@ -5,7 +5,7 @@ image:
 nginxImage:
   repository: docker.io/nginxinc/nginx-unprivileged
   pullPolicy: IfNotPresent
-  tag: 1.29.0@sha256:1e1d77c1d72274b26c0e6272b121b7ad5e55bf395cd5cd848c38828d321c1cb6
+  tag: 1.29.0@sha256:502f1c37b8f59632f42cc615a5bb4709bb8e1cbc0e728118496361dfbc4302af
 imaginaryImage:
   repository: tccr.io/tccr/nextcloud-imaginary
   pullPolicy: IfNotPresent