chore(deps): bump golang from 1.18.1-alpine to 1.20.1-alpine

Bumps golang from 1.18.1-alpine to 1.20.1-alpine.

---
updated-dependencies:
- dependency-name: golang
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Dockerfile

@@ -4,7 +4,7 @@ ARG             VCS_REF
 ARG             VERSION
 
 # build
-FROM            golang:1.18.1-alpine as builder
+FROM            golang:1.20.1-alpine as builder
 RUN             apk add --no-cache git gcc musl-dev make
 ENV             GO111MODULE=on
 WORKDIR         /go/src/moul.io/prefix