chore(deps): update container image cthulhoo/ttrss-web-nginx to latest@a857201 by renovate (#26848)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| cthulhoo/ttrss-web-nginx | digest | `21c1503` -> `a857201` |

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charts/stable/tt-rss/values.yaml

@@ -5,7 +5,7 @@ image:
 nginxImage:
   repository: cthulhoo/ttrss-web-nginx
   pullPolicy: IfNotPresent
-  tag: latest@sha256:21c1503eff6ca68278e9a33998ebbd1fd796b9173c1ce7ea69c77ec8cb506e62
+  tag: latest@sha256:a8572017cc6a4f3b996796038284364d276d6364007a31b38abba832b1ae9e06
 updaterImage:
   repository: cthulhoo/ttrss-fpm-pgsql-static
   pullPolicy: IfNotPresent