chore(deps): update container image linuxserver/calibre-web to version-0.6.21@b28792b (#15631)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
|
[linuxserver/calibre-web](https://togithub.com/linuxserver/docker-calibre-web/packages)
([source](https://togithub.com/linuxserver/docker-calibre-web)) | digest
| `2e223f2` -> `b28792b` |

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charts/stable/calibre-web/Chart.yaml

@@ -1,7 +1,7 @@
 kubeVersion: ">=1.24.0"
 apiVersion: v2
 name: calibre-web
-version: 15.0.14
+version: 15.0.15
 appVersion: 0.6.21
 description:
   Calibre-Web is a web app providing a clean interface for browsing, reading

charts/stable/calibre-web/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: linuxserver/calibre-web
   pullPolicy: IfNotPresent
-  tag: version-0.6.21@sha256:2e223f2c5195b98e2bd377dea7aaf5acc7dd9750936cf61a92c28a668b32b33f
+  tag: version-0.6.21@sha256:b28792b96f1d91a8dd4d485cfe1a5eb1160da90e46a8ca67f8d328cb98deda32
 securityContext:
   container:
     readOnlyRootFilesystem: false