chore: downgrade go version 1.20

Dockerfile

@@ -1,5 +1,4 @@
-#FROM golang:1.20-alpine AS builder
-FROM repository.umisen.com/external/golang:latest AS builder
+FROM golang:alpine AS builder
 
 ENV GO111MODULE on
 ENV CGO_ENABLED 0
@@ -13,10 +12,7 @@ COPY . .
 RUN go mod download
 RUN go build -ldflags '-s -w' -o server .
 
-#FROM alpine:latest
-FROM repository.umisen.com/external/alpine:latest
-
-RUN sed -i 's/dl-cdn.alpinelinux.org/mirrors.tuna.tsinghua.edu.cn/g' /etc/apk/repositories && apk add curl
+FROM alpine:latest
 
 ENV TZ Asia/Shanghai