Update rmcrackan/libation Docker tag to v12.8.0 (#2219)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [rmcrackan/libation](https://github.com/rmcrackan/Libation) | minor | `12.7.5` -> `12.8.0` |

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### Release Notes

<details>
<summary>rmcrackan/Libation (rmcrackan/libation)</summary>

### [`v12.8.0`](https://github.com/rmcrackan/Libation/releases/tag/v12.8.0): Libation 12.8

[Compare Source](https://github.com/rmcrackan/Libation/compare/v12.7.5...v12.8.0)

- New feature: Add dark mode to Classic
- New setting: Allow users to choose whether Libation imports Audible Plus titles
- New feature [#&#8203;1436](https://github.com/rmcrackan/Libation/issues/1436) : Add "Download split by chapters" context menu item
- Bug fix [#&#8203;1473](https://github.com/rmcrackan/Libation/issues/1473) : Fix LibationCli reusing content licenses
- Bug fix [#&#8203;1470](https://github.com/rmcrackan/Libation/issues/1470) : Fix PDF validation error

Thanks to [@&#8203;Mbucari](https://github.com/Mbucari)

[Libation](https://github.com/rmcrackan/Libation) is a free, open source audible library manager. Decrypt, backup, organize, and search your audible library

I intend to keep Libation free and open source, but if you want to [leave a tip](https://paypal.me/mcrackan?locale.x=en_us), who am I to argue?

</details>

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### Configuration

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🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied.

♻ **Rebasing**: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update again.

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Reviewed-on: https://gitea.alexlebens.dev/alexlebens/infrastructure/pulls/2219
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
Co-committed-by: Renovate Bot <renovate-bot@alexlebens.net>

clusters/cl01tl/helm/libation/values.yaml

@@ -16,7 +16,7 @@ libation:
         main:
           image:
             repository: rmcrackan/libation
-            tag: 12.7.5
+            tag: 12.8.0
             pullPolicy: IfNotPresent
           env:
             - name: SLEEP_TIME