chore(helm): update image docker.io/linuxserver/calibre-web digest to eb9f821 (#28403)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/linuxserver/calibre-web | digest | `d4bc450` -> `eb9f821` |

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

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charts/stable/calibre-web/Chart.yaml

@@ -34,4 +34,4 @@ sources:
   - https://github.com/truecharts/charts/tree/master/charts/stable/calibre-web
   - https://hub.docker.com/r/linuxserver/calibre-web
 type: application
-version: 20.2.3
+version: 20.2.4

charts/stable/calibre-web/values.yaml

@@ -1,7 +1,7 @@
 image:
   repository: docker.io/linuxserver/calibre-web
   pullPolicy: IfNotPresent
-  tag: version-0.6.23@sha256:d4bc450cf46421595e7f27d4413473758d0d9025b9afbba0113c71599144e709
+  tag: version-0.6.23@sha256:eb9f821d04b57bb565853e6c61b33b64968f32cc08cabe64beec423a7fffd51f
 securityContext:
   container:
     readOnlyRootFilesystem: false