chore(deps): update gitroomhq/postiz-app to v2.19.0 (#4122)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| ghcr.io/gitroomhq/postiz-app | minor | `v2.18.0` → `v2.19.0` |
| [gitroomhq/postiz-app](https://github.com/gitroomhq/postiz-app) | minor | `v2.18.0` → `v2.19.0` |

---

### Release Notes

<details>
<summary>gitroomhq/postiz-app (gitroomhq/postiz-app)</summary>

### [`v2.19.0`](https://github.com/gitroomhq/postiz-app/releases/tag/v2.19.0): TikTok improvements, Instagram multiple stories &amp; compression

[Compare Source](https://github.com/gitroomhq/postiz-app/compare/v2.18.0...v2.19.0)

#### Features

- Remove upload throttle
- Compression
- Better indexes
- Logout
- TikTok fixes and ordering
- Instagram multiple stories
- MCP on route
- Rotate API key
- Post missing modal
- Bot nickname

#### Fixes

- Rate limiting to only POST requests
- Reddit fix
- Email and draft fixes
- Upload-from-url file extension fix

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 **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 these updates again.

---

 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box

---

This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
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Reviewed-on: #4122
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
Co-committed-by: Renovate Bot <renovate-bot@alexlebens.net>

clusters/cl01tl/helm/postiz/Chart.yaml

@@ -41,4 +41,4 @@ dependencies:
     repository: oci://harbor.alexlebens.net/helm-charts
 icon: https://cdn.jsdelivr.net/gh/selfhst/icons/png/postiz.png
 # renovate: datasource=github-releases depName=gitroomhq/postiz-app
-appVersion: v2.18.0
+appVersion: v2.19.0

clusters/cl01tl/helm/postiz/values.yaml

@@ -9,7 +9,7 @@ postiz:
         main:
           image:
             repository: ghcr.io/gitroomhq/postiz-app
-            tag: v2.18.0
+            tag: v2.19.0
             pullPolicy: IfNotPresent
           env:
             - name: MAIN_URL