chore(deps): update container image cthulhoo/ttrss-web-nginx to latest@c918697 by renovate (#24758)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| cthulhoo/ttrss-web-nginx | digest | `351c9ef` -> `c918697` |

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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@sha256:351c9ef9f491b68e42bc6da654efcc65bc278330b95c478807a7aae26882a86f
+  tag: latest@sha256:c918697c8072c952929874c8d026c83ca06ccfde928ec2fc0c8ddfed1784dc05
 updaterImage:
   repository: cthulhoo/ttrss-fpm-pgsql-static
   pullPolicy: IfNotPresent