chore(deps): update container image wekanteam/wekan to v7.21@d8c16e3 (#15419)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [wekanteam/wekan](https://togithub.com/wekan/wekan) | minor | `v7.20`
-> `v7.21` |

---

> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
Dashboard for more information.

---

### Release Notes

<details>
<summary>wekan/wekan (wekanteam/wekan)</summary>

###
[`v7.21`](https://togithub.com/wekan/wekan/blob/HEAD/CHANGELOG.md#v721-2023-11-27-WeKan--release)

[Compare Source](https://togithub.com/wekan/wekan/compare/v7.20...v7.21)

This release adds the following updates:

- [Updated
dependencies](https://togithub.com/wekan/wekan/commit/fef0c0e490ef0d90b6504074312bf827ff5f2d61).
    Thanks to developers of dependencies.

Thanks to above GitHub users for their contributions and translators for
their translations.

</details>

---

### Configuration

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🚦 **Automerge**: Enabled.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
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charts/stable/wekan/Chart.yaml

@@ -1,5 +1,5 @@
 apiVersion: v2
-appVersion: "7.20"
+appVersion: v7.21
 dependencies:
   - name: common
     repository: https://library-charts.truecharts.org
@@ -24,7 +24,7 @@ sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/wekan
   - https://github.com/wekan/wekan
   - https://wekan.github.io/
-version: 10.2.0
+version: 10.3.0
 annotations:
   truecharts.org/category: productivity
   truecharts.org/SCALE-support: "true"

charts/stable/wekan/values.yaml

@@ -1,6 +1,6 @@
 image:
   repository: wekanteam/wekan
-  tag: v7.20@sha256:59089fe031b2914af487f02b58b3717c3ff1c60ff2ce1b008517f215804a6049
+  tag: v7.21@sha256:d8c16e3837c752eb259f120a501c139a4481c2fe69a070ef139293f2e5691cf7
   pullPolicy: IfNotPresent
 service:
   main: