chore(firefox): update image ghcr.io/linuxserver/firefox digest to a9e20f7 (#48833)

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 | `108231e` → `a9e20f7` |

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charts/stable/firefox/Chart.yaml

@@ -36,5 +36,5 @@ sources:
   - https://github.com/linuxserver/docker-firefox
   - https://github.com/trueforge-org/truecharts/tree/master/charts/stable/firefox
 type: application
-version: 39.0.1
+version: 39.0.2
 

charts/stable/firefox/values.yaml

@@ -2,7 +2,7 @@
 image:
   repository: ghcr.io/linuxserver/firefox
   pullPolicy: IfNotPresent
-  tag: 1151.0.3@sha256:108231e182accad56e0db0e22eca309df125e066b91cea28c3bc11a1f9338297
+  tag: 1151.0.3@sha256:a9e20f79cd6bfe7c4b2cfc3cbf4b31914ac12822709486a0cf2ae6cd814bb994
 securityContext:
   container:
     readOnlyRootFilesystem: false