chore(helm): update image ghcr.io/linuxserver/firefox digest to a9b00b8 (#33793)

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 | `f998867` -> `a9b00b8` |

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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: 23.0.3
+version: 23.0.4

charts/stable/firefox/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: ghcr.io/linuxserver/firefox
   pullPolicy: IfNotPresent
-  tag: 136.0.4@sha256:f998867a11edbe93bb3af19586d095decb391d61798f17fc1580d93ae35fe661
+  tag: 136.0.4@sha256:a9b00b8df4b92732476b0014c04716f0eaec247d7939fbd859cdaeeb3efd435c
 securityContext:
   container:
     readOnlyRootFilesystem: false