chore(helm): update image docker.io/cthulhoo/ttrss-web-nginx digest to 997301a (#31847)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/cthulhoo/ttrss-web-nginx | digest | `88748a1` -> `997301a` |

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charts/stable/tt-rss/Chart.yaml

@@ -34,4 +34,4 @@ sources:
   - https://hub.docker.com/r/cthulhoo/ttrss-fpm-pgsql-static
   - https://hub.docker.com/r/cthulhoo/ttrss-web-nginx
 type: application
-version: 18.5.5
+version: 18.5.6

charts/stable/tt-rss/values.yaml

@@ -5,7 +5,7 @@ image:
 nginxImage:
   repository: docker.io/cthulhoo/ttrss-web-nginx
   pullPolicy: IfNotPresent
-  tag: latest@sha256:88748a124a7fefd149e46d758de56298ec0f731fb5955bd1d47204fcdc456466
+  tag: latest@sha256:997301a258ee6012ef165fe0dcc345d5792e48784aa17bb9f4af7002a701123a
 updaterImage:
   repository: docker.io/cthulhoo/ttrss-fpm-pgsql-static
   pullPolicy: IfNotPresent