chore(helm): update image docker.io/outlinewiki/outline digest to c0818e8 (#40688)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
|
[docker.io/outlinewiki/outline](https://redirect.github.com/outline/outline)
| digest | `659a8bf` -> `c0818e8` |

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charts/stable/outline/Chart.yaml

@@ -46,5 +46,5 @@ sources:
   - https://github.com/trueforge-org/truecharts/tree/master/charts/stable/outline
   - https://hub.docker.com/r/outlinewiki/outline
 type: application
-version: 16.21.1
+version: 16.21.2
 

charts/stable/outline/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: docker.io/outlinewiki/outline
   pullPolicy: IfNotPresent
-  tag: 0.87.4@sha256:659a8bf588ef2d914ef4e519409f38e472145369383c0a5aa89b286b4dfe860c
+  tag: 0.87.4@sha256:c0818e82d54861793e393ee77178b4ce9bf88abf11abb91740c677cd4f6e9524
 service:
   main:
     ports: