chore(tt-rss): update image ghcr.io/tt-rss/tt-rss-web-nginx digest to 28d18b7 (#50003)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/tt-rss/tt-rss-web-nginx | digest | `7cb50d3` → `28d18b7` |

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charts/stable/tt-rss/Chart.yaml

@@ -37,5 +37,5 @@ sources:
   - https://git.tt-rss.org/fox/tt-rss
   - https://github.com/trueforge-org/truecharts/tree/master/charts/stable/tt-rss
 type: application
-version: 21.6.5
+version: 21.6.6
 

charts/stable/tt-rss/values.yaml

@@ -6,7 +6,7 @@ image:
 nginxImage:
   repository: ghcr.io/tt-rss/tt-rss-web-nginx
   pullPolicy: IfNotPresent
-  tag: latest@sha256:7cb50d3d52a6417148e1c118f9b399b0e636a203b117d03c94bfcc0b7ed5e2c0
+  tag: latest@sha256:28d18b7a5093956f9bf77ea5d434e0c29e5b29a3d8a9dbbdbdb1546ce6e0a133
 updaterImage:
   repository: ghcr.io/tt-rss/tt-rss
   pullPolicy: IfNotPresent