chore(common): update image oci.trueforge.org/containerforge/ubuntu digest to c21fcd8 (#48984)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
|
[oci.trueforge.org/containerforge/ubuntu](https://ghcr.io/trueforge-org/ubuntu)
([source](https://hub.docker.com/_/ubuntu)) | digest | `17312da` →
`c21fcd8` |

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charts/library/common/Chart.yaml

@@ -45,5 +45,5 @@ sources:
   - https://github.com/trueforge-org/truecharts/tree/master/charts/library/common
   - https://hub.docker.com/_/
 type: library
-version: 29.5.3
+version: 29.5.5
 

charts/library/common/values.yaml

@@ -593,7 +593,7 @@ alpineImage:
 
 ubuntuImage:
   repository: oci.trueforge.org/containerforge/ubuntu
-  tag: "26.4@sha256:17312da6b52fe7ab6e3bdc8e4a1f99df63c2494b2bad4f4b634a9065d585898e"
+  tag: "26.4@sha256:c21fcd861c5eccd1dec9c7b9a88647fc3a22585c3d7cf77ba48129844e7a584b"
   pullPolicy: IfNotPresent
 
 scratchImage:
@@ -608,7 +608,7 @@ kubectlImage:
 
 wgetImage:
   repository: oci.trueforge.org/containerforge/ubuntu
-  tag: "26.4@sha256:17312da6b52fe7ab6e3bdc8e4a1f99df63c2494b2bad4f4b634a9065d585898e"
+  tag: "26.4@sha256:c21fcd861c5eccd1dec9c7b9a88647fc3a22585c3d7cf77ba48129844e7a584b"
   pullPolicy: IfNotPresent
 
 yqImage: