chore(helm): update image ghcr.io/linuxserver/tvheadend digest to 993b1a0 (#31578)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/linuxserver/tvheadend | digest | `c5e8887` -> `993b1a0` |

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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: 21.5.1
+version: 21.5.2

charts/stable/tvheadend/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: ghcr.io/linuxserver/tvheadend
   pullPolicy: IfNotPresent
-  tag: latest@sha256:c5e8887b45464046d62bce754de06286989c436ea77c445d3efeb8cc4ed8c3cf
+  tag: latest@sha256:993b1a02b6a7fd009bb2741c63126e2a8b775f7638f5a9e2702bc2cc4d799c61
 service:
   main:
     ports: