chore(helm): update image docker.io/machines/filestash digest to 1a8ebf4 (#32423)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/machines/filestash | digest | `f06cc37` -> `1a8ebf4` |

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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: 8.5.14
+version: 8.5.15

charts/stable/filestash/values.yaml

@@ -1,6 +1,6 @@
 image:
   repository: docker.io/machines/filestash
-  tag: latest@sha256:f06cc3719c38aabe0983a520e0f2d0848c582628879cca9c325769be91d23971
+  tag: latest@sha256:1a8ebf414713ae5f6ca3bb2331efe743e489f83b546a80632ee717da6c80feb8
   pullPolicy: IfNotPresent
 
 securityContext: