fix: integrate docker file with go build

Dockerfile

@@ -1,13 +1,26 @@
-FROM alpine:latest as builder
+FROM golang:1.22-alpine as builder
+
+ADD . ./src
+
+WORKDIR /go/src
 
 RUN sed -i 's/dl-cdn.alpinelinux.org/mirrors.ustc.edu.cn/g' /etc/apk/repositories \
-    && apk --no-cache add ca-certificates
+    && apk --no-cache add ca-certificates \
+    && go env -w GOPROXY='https://goproxy.cn,direct' \
+    && go mod tidy \
+    && CGO_ENABLED=0 GOOS="linux" GOARCH="amd64" \
+        go build \
+        -ldflags="-s -w" \
+        -tags timetzdata \
+        -v \
+        -o /app \
+        ./cmd/cert-exporter
 
 FROM scratch as production
 
 ENV TZ="Asia/Shanghai"
 
-COPY ./build/app /
+COPY --from=builder /app /
 COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
 
 CMD ["/app"]