build(deploy): 更新 Dockerfile 中的镜像源

- 将 ARG REGISTRY 设置为阿里云镜像仓库
- 更新 FROM 行的镜像源为 ${REGISTRY}/alpine:3.16
- 优化 apk repositories 的修改方式

deploy/build/Dockerfile

@@ -1,4 +1,4 @@
-ARG REGISTRY=docker.io
+ARG REGISTRY=registry.cn-hangzhou.aliyuncs.com
 FROM ${REGISTRY}/golang:1.24-alpine AS builder
 RUN set -eux && sed -i 's/dl-cdn.alpinelinux.org/mirrors.ustc.edu.cn/g' /etc/apk/repositories && apk add --no-cache git
 
@@ -20,7 +20,7 @@ RUN export GOPROXY=https://goproxy.cn,direct && go mod tidy && go build -ldflags
 RUN mv config /data/app/bin/
 
 
-FROM registry.cn-hangzhou.aliyuncs.com/alpine:3.16
+FROM ${REGISTRY}/alpine:3.16
 RUN set -eux && sed -i 's/dl-cdn.alpinelinux.org/mirrors.ustc.edu.cn/g' /etc/apk/repositories