improve Dockerfile

Dockerfile

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1.7
 
-FROM --platform=$BUILDPLATFORM golang:1.22-alpine AS builder
+FROM golang:1.26-alpine AS builder
 WORKDIR /src
 
 RUN apk add --no-cache ca-certificates tzdata
@@ -18,7 +18,7 @@ RUN XTEVE_VERSION="$(awk '/^#### /{print $2; exit}' changelog-beta.md)" \
   && CGO_ENABLED=0 GOOS=$TARGETOS GOARCH=$TARGETARCH \
   go build -trimpath -ldflags="-s -w -X main.Version=${XTEVE_VERSION}" -o /out/xteve ./xteve.go
 
-FROM alpine:3.20
+FROM alpine:3.23
 
 RUN apk add --no-cache ca-certificates tzdata \
   && addgroup -S xteve \