chore(helm): update image ghcr.io/linuxserver/tvheadend digest to 251808d (#32808)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/linuxserver/tvheadend | digest | `39bcc2f` -> `251808d` |

Add the preset `:preserveSemverRanges` to your config if you don't want
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charts/stable/tvheadend/Chart.yaml

@@ -35,4 +35,4 @@ sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/tvheadend
   - https://github.com/tvheadend/tvheadend
 type: application
-version: 21.5.4
+version: 21.5.5

charts/stable/tvheadend/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: ghcr.io/linuxserver/tvheadend
   pullPolicy: IfNotPresent
-  tag: latest@sha256:39bcc2f5b065eeaf49c4cf280888433d09bb25a3ab786069c0c3df72ede3e101
+  tag: latest@sha256:251808d47d818c6eac5ffe0943bb3c65e49d641dbc735a5b3cb7b183d4508c27
 service:
   main:
     ports: