chore(package): update quay.io/kairos/kairos-init docker tag to v0.4.9 (#408)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| quay.io/kairos/kairos-init | stage | patch | `v0.4.8` -> `v0.4.9` |

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images/kairos-ubuntu/Dockerfile

@@ -1,6 +1,6 @@
 # See https://kairos.io/docs/reference/kairos-factory/ for more details.
 
-FROM quay.io/kairos/kairos-init:v0.4.8@sha256:0b8c5c0a633edcc76fd3f76ffaf927c7c170f114520d52afb59b22728e1ce5d1 AS kairos-init
+FROM quay.io/kairos/kairos-init:v0.4.9@sha256:66aa70c19d598b96a58b74e3eaa42bc61ce3ba8f20fc93fda586745786508060 AS kairos-init
 
 FROM ubuntu:24.04@sha256:6015f66923d7afbc53558d7ccffd325d43b4e249f41a6e93eef074c9505d2233 AS base-kairos
 LABEL org.opencontainers.image.title="A custom Ubuntu-based Kairos image."