Revert "Docker build use 1.20 go"

This reverts commit cd1d000860.

.github/docker/Dockerfile

@@ -1,5 +1,5 @@
 # syntax=docker/dockerfile:1
-FROM --platform=$BUILDPLATFORM golang:1.20-alpine AS build
+FROM --platform=$BUILDPLATFORM golang:alpine AS build
 WORKDIR /src
 COPY . .
 ARG TARGETOS TARGETARCH