chore(helm): update image xwiki digest to b9e8f2c (#28022)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| xwiki | digest | `28f8fab` -> `b9e8f2c` |

Add the preset `:preserveSemverRanges` to your config if you don't want
to pin your dependencies.

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charts/stable/xwiki/Chart.yaml

@@ -33,4 +33,4 @@ sources:
   - https://github.com/xwiki/xwiki-docker
   - https://hub.docker.com/_/xwiki
 type: application
-version: 14.6.7
+version: 14.6.8

charts/stable/xwiki/values.yaml

@@ -1,6 +1,6 @@
 image:
   repository: xwiki
-  tag: 16.8.0-postgres-tomcat@sha256:28f8fabd935d9c7da43f3091625cd5aa6af105772dacd82752a8acb3db8008a4
+  tag: 16.8.0-postgres-tomcat@sha256:b9e8f2c84ddacf75b5da038f3df258e776b6d745128935663b81859015dff478
   pullPolicy: IfNotPresent
 service:
   main: