chore(deps): update container image ghcr.io/linuxserver/tvheadend to latest@ffc7abc by renovate (#26740)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/linuxserver/tvheadend | digest | `db35cf6` -> `ffc7abc` |

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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: 21.1.14
+version: 21.1.15

charts/stable/tvheadend/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: ghcr.io/linuxserver/tvheadend
   pullPolicy: IfNotPresent
-  tag: latest@sha256:db35cf661d7da46665334349a9ac33ca06df5ea682a26ef16f006a14b18bc4cb
+  tag: latest@sha256:ffc7abc6fbe39751ddebc8c63b865ace94d7a3194409c97c15cf1de6e180dc6c
 service:
   main:
     ports: