fix(jellyfin): Fix Jellyfin transcode dir mount location (#41821)

**Description**
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The transcode dir was being mounted to `/config/transcodes` , while the
correct location (wrt the default Jellyfin config) is
`/cache/transcodes`.

This means that, until now, regardless of what was configured in the
chart values, transcoding was actually performed on the node disk (for
example, on Talos, that is the `EPHEMERAL` partition), instead of, say,
in a ramdisk as it is often configured to be.

⚒️ Fixes  # <!--(issue)-->

**⚙️ Type of change**

- [ ] ⚙️ Feature/App addition
- [x] 🪛 Bugfix
- [ ] ⚠️ Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [ ] 🔃 Refactor of current code
- [ ] 📜 Documentation Changes

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**✔️ Checklist:**

- [x] ⚖️ My code follows the style guidelines of this project
- [x] 👀 I have performed a self-review of my own code
- [ ] #️⃣ I have commented my code, particularly in hard-to-understand
areas
- [ ] 📄 I have made changes to the documentation
- [ ] 🧪 I have added tests to this description that prove my fix is
effective or that my feature works
- [x] ⬆️ I increased versions for any altered app according to semantic
versioning
- [x] I made sure the title starts with `feat(chart-name):`,
`fix(chart-name):`, `chore(chart-name):`, `docs(chart-name):` or
`fix(docs):`

**➕ App addition**

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- [ ] 🖼️ I have added an icon in the Chart's root directory called
`icon.png`

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---------

Signed-off-by: astro-stan <36302090+astro-stan@users.noreply.github.com>

charts/stable/jellyfin/Chart.yaml

@@ -40,5 +40,4 @@ sources:
   - https://github.com/trueforge-org/truecharts/tree/master/charts/stable/jellyfin
   - https://hub.docker.com/r/alpine/socat
 type: application
-version: 21.12.8
-
+version: 21.12.9

charts/stable/jellyfin/values.yaml

@@ -30,7 +30,7 @@ persistence:
     type: "emptyDir"
   transcode:
     enabled: true
-    mountPath: "/config/transcodes"
+    mountPath: "/cache/transcodes"
     type: "emptyDir"
 
 securityContext: