chore(helm): update image lscr.io/linuxserver/heimdall digest to bfe9759 (#33535)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| lscr.io/linuxserver/heimdall | digest | `bb15f31` -> `bfe9759` |

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

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charts/stable/heimdall/Chart.yaml

@@ -32,4 +32,4 @@ sources:
   - https://github.com/linuxserver/Heimdall/
   - https://github.com/truecharts/charts/tree/master/charts/stable/heimdall
 type: application
-version: 23.4.7
+version: 23.4.8

charts/stable/heimdall/values.yaml

@@ -1,6 +1,6 @@
 image:
   repository: lscr.io/linuxserver/heimdall
-  tag: 2.6.3@sha256:bb15f31a95c2df5cf51b92655ede70c41459a734368f9e9dc18d8cd585de24d9
+  tag: 2.6.3@sha256:bfe975986b6d0cbe1e18d8dd0bef679a5904f3b34ea6494bd5ba18e142894152
   pullPolicy: IfNotPresent
 service:
   main: