chore(helm): update image ghcr.io/elfhosted/emby digest to b21825c (#33363)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/elfhosted/emby | digest | `556d537` -> `b21825c` |

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charts/stable/emby/Chart.yaml

@@ -35,4 +35,4 @@ sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/emby
   - https://hub.docker.com/r/alpine/socat
 type: application
-version: 22.4.20
+version: 22.4.21

charts/stable/emby/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: ghcr.io/elfhosted/emby
   pullPolicy: IfNotPresent
-  tag: 4.9.0.42@sha256:556d5372e7f2a8283d7dd3c9a256dfba8f36d6ffa14ed556b2bc19a79fe5b43b
+  tag: 4.9.0.42@sha256:b21825c1f7f484f9ee5b834275be55f2272997e22cde0209aa755d1ad593bf71
 broadcastProxyImage:
   repository: docker.io/alpine/socat
   pullPolicy: IfNotPresent