chore(deps): update valkey docker tag to v0.4.0 (#4572)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [valkey](https://github.com/valkey-io/valkey) | minor | `0.3.0` → `0.4.0` |

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### Configuration

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This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0My41OS4yIiwidXBkYXRlZEluVmVyIjoiNDMuNTkuMiIsInRhcmdldEJyYW5jaCI6Im1haW4iLCJsYWJlbHMiOlsiaW1hZ2UiXX0=-->

Reviewed-on: #4572
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
Co-committed-by: Renovate Bot <renovate-bot@alexlebens.net>

clusters/cl01tl/helm/matrix-synapse/Chart.lock

@@ -22,10 +22,10 @@ dependencies:
   version: 7.8.0
 - name: valkey
   repository: oci://harbor.alexlebens.net/helm-charts
-  version: 0.3.0
+  version: 0.4.0
 - name: valkey
   repository: oci://harbor.alexlebens.net/helm-charts
-  version: 0.3.0
+  version: 0.4.0
 - name: volsync-target
   repository: oci://harbor.alexlebens.net/helm-charts
   version: 0.8.0
@@ -38,5 +38,5 @@ dependencies:
 - name: volsync-target
   repository: oci://harbor.alexlebens.net/helm-charts
   version: 0.8.0
-digest: sha256:a22b498177f0b5339240ab6c55801d65d5c7921b2de0c0b6f0c2d3eb69e0ff99
-generated: "2026-03-09T22:05:01.925279941Z"
+digest: sha256:fc6e3a04b828daf3a0861aec6a7a6d1c9a45fabaf29abd3fb3be2e8db4d0875b
+generated: "2026-03-09T23:08:07.610958823Z"