chore(helm): update image lscr.io/linuxserver/heimdall digest to b8a3974 (#32823)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| lscr.io/linuxserver/heimdall | digest | `4530bb8` -> `b8a3974` |

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: 23.4.5
+version: 23.4.6

charts/stable/heimdall/values.yaml

@@ -1,6 +1,6 @@
 image:
   repository: lscr.io/linuxserver/heimdall
-  tag: 2.6.3@sha256:4530bb848f38bcb37c07157745d193988c512d9a48f33c93aa6e6b9280679054
+  tag: 2.6.3@sha256:b8a397409596040a46463b3ac70e0d21a2ae56a8edeb30b94dfe7cfb1db69cd1
   pullPolicy: IfNotPresent
 service:
   main: