chore(helm): update image docker.io/machines/filestash digest to b53ec51 (#33116)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/machines/filestash | digest | `64cc5b0` -> `b53ec51` |

Add the preset `:preserveSemverRanges` to your config if you don't want
to pin your dependencies.

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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: 8.5.20
+version: 8.5.21

charts/stable/filestash/values.yaml

@@ -1,6 +1,6 @@
 image:
   repository: docker.io/machines/filestash
-  tag: latest@sha256:64cc5b0c6e96ae327d9ad41190b4ece536605d421cb9867694cd501643b04a55
+  tag: latest@sha256:b53ec51b196230dad74f2b2a5a47a33532a7a6c452b06cc9e9226e534e7a3710
   pullPolicy: IfNotPresent
 
 securityContext: