⬆️ Update Alpine base image to v3.18.4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
alpine		patch	3.18.3 -> 3.18.4
alpine	final	patch	3.18.3 -> 3.18.4
amd64/alpine		patch	3.18.3 -> 3.18.4
arm32v6/alpine		patch	3.18.3 -> 3.18.4
arm32v7/alpine		patch	3.18.3 -> 3.18.4
arm64v8/alpine		patch	3.18.3 -> 3.18.4
i386/alpine		patch	3.18.3 -> 3.18.4

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