Dockerfile: update to alpine 3.21

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Dockerfile

@@ -1,7 +1,7 @@
 # syntax=docker/dockerfile:1
 
 ARG BASE_VARIANT=alpine
-ARG ALPINE_VERSION=3.20
+ARG ALPINE_VERSION=3.21
 ARG BASE_DEBIAN_DISTRO=bookworm
 
 ARG GO_VERSION=1.23.5

dockerfiles/Dockerfile.authors

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1
 
-ARG ALPINE_VERSION=3.20
+ARG ALPINE_VERSION=3.21
 
 FROM alpine:${ALPINE_VERSION} AS gen
 RUN apk add --no-cache bash git

dockerfiles/Dockerfile.dev

@@ -1,7 +1,7 @@
 # syntax=docker/dockerfile:1
 
 ARG GO_VERSION=1.23.5
-ARG ALPINE_VERSION=3.20
+ARG ALPINE_VERSION=3.21
 
 ARG BUILDX_VERSION=0.17.1
 FROM docker/buildx-bin:${BUILDX_VERSION} AS buildx

dockerfiles/Dockerfile.lint

@@ -1,7 +1,7 @@
 # syntax=docker/dockerfile:1
 
 ARG GO_VERSION=1.23.5
-ARG ALPINE_VERSION=3.20
+ARG ALPINE_VERSION=3.21
 ARG GOLANGCI_LINT_VERSION=v1.62.2
 
 FROM golangci/golangci-lint:${GOLANGCI_LINT_VERSION}-alpine AS golangci-lint

dockerfiles/Dockerfile.vendor

@@ -1,7 +1,7 @@
 # syntax=docker/dockerfile:1
 
 ARG GO_VERSION=1.23.5
-ARG ALPINE_VERSION=3.20
+ARG ALPINE_VERSION=3.21
 ARG MODOUTDATED_VERSION=v0.8.0
 
 FROM golang:${GO_VERSION}-alpine${ALPINE_VERSION} AS base