chore(helm): update image docker.io/machines/filestash digest to a4cb390 (#30473)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/machines/filestash | digest | `461ba36` -> `a4cb390` |

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charts/stable/filestash/Chart.yaml

@@ -36,4 +36,4 @@ sources:
   - https://hub.docker.com/r/machines/filestash
   - https://www.filestash.app/
 type: application
-version: 8.4.0
+version: 8.4.1

charts/stable/filestash/values.yaml

@@ -1,6 +1,6 @@
 image:
   repository: docker.io/machines/filestash
-  tag: latest@sha256:461ba360dd4cc681b95f2439f8e7e4f10c4fa402cb2f1e6a0863b19ea4c6cc53
+  tag: latest@sha256:a4cb390f3c48d15049fcc827009fcd14b7ccca861380bbe4aa6263bfcf282ae9
   pullPolicy: IfNotPresent
 
 securityContext: