chore(helm): update image ghcr.io/linuxserver/firefox digest to 28b8477 (#30617)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
|
[ghcr.io/linuxserver/firefox](https://redirect.github.com/linuxserver/docker-firefox/packages)
([source](https://redirect.github.com/linuxserver/docker-firefox)) |
digest | `9c68d48` -> `28b8477` |

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charts/stable/firefox/Chart.yaml

@@ -33,4 +33,4 @@ sources:
   - https://github.com/linuxserver/docker-firefox
   - https://github.com/truecharts/charts/tree/master/charts/stable/firefox
 type: application
-version: 20.1.0
+version: 20.1.1

charts/stable/firefox/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: ghcr.io/linuxserver/firefox
   pullPolicy: IfNotPresent
-  tag: 133.0.3@sha256:9c68d48a040f2c753349135bae59dc6081ed3eddb3b8d161197062adee2d028f
+  tag: 133.0.3@sha256:28b84771a1ce579e72cf47024b228204e98cbcd69a103ec1b8859a9b619e8c43
 securityContext:
   container:
     readOnlyRootFilesystem: false